
Troubleshooting Homebrew

Introduction

Troubleshooting Homebrew Methodology

**Step 1:**Identifying the Problem

A quick overview of evaluating beer

Most common off flavors and aromas

Most Common Non-Fault Beer Flavors

Malt

Hops

Yeast

Water

Training Your Senses

Getting Acquainted with the Guidelines

Putting it all together

**Step 2:**Establishing the Theory

Common causes of off flavors and aromas

Common causes of brewing process faults

Determining Cause

**Step 3:**Create a Plan of Action

Correcting Common Causes of off flavors and aroma

Correcting Common Causes of Brewing Process Faults

Correcting General Infection Issues

Correcting General Fermentation Issues

**Step 4:**Test the Theory

Plan for Failure

**Step 5:**Verify the Result

Self-Evaluation

Always get a second opinion

**Step 6:**Documenting your findings

Appendix I: Late extract method  
Appendix II: Making a stir plate for yeast starters  
Appendix III: Making Homemade caramels for taste/aroma evaluation

Introduction

There are many books on the market to teach you the basics about brewing and even more so on how to up your game in the world of homebrew. There are books on hops, grains, yeast, and water. There are books on recipe formulation and styles, pairing beer with food, and even how to taste and evaluate beer. There are also books that try to help you troubleshoot your beer. That is what this book will attempt to do as well, if you are a seasoned homebrewer, this book may not be advanced enough for you. This book is geared a lot more to the novice and intermediate brewers and possibly for people interested in becoming a BJCP judge. As an IT Professional, I am very familiar with the 6 steps of troubleshooting; Identify, Theorize, Plan, Test, Verify, and Document. As a homebrewer and BJCP judge, I know that there is a need for a standardized process of troubleshooting that goes beyond just "here are the major faults and the most common cause", because having a process helps build consistency. Consistency leads to consistent results, and that is always what we strive for. While at first it may appear that troubleshooting your beer is as simple as "It's infected, so check your sanitation" there is more to a good troubleshooting process than simply that. Sometimes that infection is not really an infection at all, but rather what you perceive as an infection is really a result of poor fermentation. I will attempt to help give you the tools to diagnose your beer. Those tools will not only be the flavors and aromas of beer faults, but also of common flavors and aromas found in beer that is not considered faults.

When I entered my first competition several years back, I won my first homebrew medal with an extract with grains recipe for a chocolate stout. It was at this point that I decided I wanted to see what being a judge all was about. I wanted to know what qualified this person to say my beer was better than that other beer in that particular style, and why. On a whim I contacted the BJCP about finding a competition that I could help out at and find out about the judging process. What they did was point me in the direction of a homebrew club about 40 miles away from my home that hosts a competition every spring. So I made the call to the organizer who instead, talked me into joining a BJCP prep course they were going to be starting in a couple of weeks. I ended up signing up for the 12 week course, and traveled to every class without fail. Now mind you, at this point I had not made the move to All-Grain. I was a craft beer lover and novice brewer who thought I knew quite a bit about beer, but in this class my eyes were opened to every style of beer in the BJCP guidelines and I realized how much a novice I really was at that point. I was pretty intimidated, but I stuck with the course and made it goal for myself to pass the exam with a minimum of 70 points on both tasting and the written essay portions of the test on my first pass through. What I had to do was work a lot more at developing my palate compared to the seasoned brewers who were in the same course. To make a long story short, I passed the exam back then with scores into the 70's. I reached my goal at that point and I was very happy. I judged my first competition a week after taking the exam, and I didn't even have my scores back yet for a few months. So my first experience with judging was trial by fire, and over 10 years later I'm still learning things at every competition. So what was the point of tell you all of this? My point is that if I can bring myself up to the standard of certified judge as a novice brewer, anyone can work to develop the knowledge and basic skills to identify a potential problem in a beer. Do you have to be a judge? Absolutely not, I know a lot of people with excellent palates, who have not taken a BJCP course in their life. I also know some judges who have worked to obtain the rank, only to lose their passion for judging and stopped caring long ago. So my point was not to say you have to get formalized training or be a judge, just that with some practice and guidance, anyone can learn to identify problems in the beer, which will be your first and most critical step in the troubleshooting process.

Troubleshooting Homebrew Methodology

Most of the time, whenever we as homebrewers, troubleshoot our beer, we taste it and come up with what is wrong based on either past experience, or something that someone else has told us about our beer. But the process of troubleshooting has some simple stages that are easy to understand and follow. Understanding the troubleshooting method will better help you pinpoint the problem yourself, and be objective about it. Since many times problems may manifest themselves in a similar manner such as off-flavors, off-aromas, or even if it's too cloudy; the causes can be different. So just because the last time your beer did not turn out because of an infection from wild yeast, that doesn't mean that every time you have an off-flavor, it's from wild yeast. Following the troubleshooting method will keep your troubleshooting process consistent and objective. This will help you better diagnose and more importantly, fix your beer.

The troubleshooting method consists of six steps. Those steps are Identify, Theorize, Plan, Test, Verify, and Document. Before we go more in-depth into how this methodology fits with homebrewing, let's look at an overview of the process.

**Identify:** Identifying what exactly the problem is. Here is where you want to develop a full understanding of the issue. In the case of beer troubleshooting, this is where your palate development will come most heavily into play. A full understanding of what your beer should be, or at least what you were trying to achieve is of great importance as well.

**Theorize** : In this step, you take your understanding of the problem and theorize the most probable cause. Based on your palate assessment of the beer, and your knowledge of what the beer was supposed to be like, you come up with a short list of the most probable causes based on the causes of that particular problem.

**Plan:** In the planning phase, you come up with a game plan to eliminate the problem. In some cases, if you are not going to brew this particular beer again and you determined the problem was in the recipe, you would quit at previous phase. But if your theory is infection or brewing process, you do want to plan how you are going to fix the problem so it does not affect future beers.

**Test:** With this phase of troubleshooting, you have to test your plan to be sure it eliminates the problem. The test phase can be brewing the same beer again with your process adjustments, or adjusting your process or equipment to correct the issue.

**Verify:** In the verify phase, you actually go back to the step 1 to be sure you do not see any signs of the problem you tried to fix. If during this phase you still see signs of contamination or your off-flavor, you go back to step 2 and eliminate your most probable cause and move to the next most probable cause. Sometimes the troubleshooting process can be a long one until you nail down the cause. At times, it can be a very obscure problem.

**Document:** This phase may not be required for most homebrewers, but in the troubleshooting method you do want to document the problem, the steps you took to fix it, and ultimately what corrected it. I don't foresee a lot of homebrewers keeping a troubleshooting log. But if you want to stick true to the method, documentation is an important stage so if you ever run across another similar problem, you can use your previous research to come up with a quick solution.

Now we have a basic understanding of the troubleshooting method, and how it can apply to us as homebrewers. Let's delve a bit deeper into the method and apply brewing specific problems and solutions. As we move forward, it should be pointed out that not every single possible answer to every single possible problem will be written about. That is the purpose behind the troubleshooting method, it gives you the tools required to think about and formulate solutions based on your individual process and equipment.

Step 1: Identifying the Problem

This is the most critical part of the troubleshooting methodology. If you are unable to identify the problem, it is impossible to move forward with finding a theory about the cause and ultimately fixing the problem. When identifying the problem, you are going to be looking at how the beer tastes, how the beer smells, and how the beer feels. In order to do this you have know how to properly evaluate a beer, and have a general knowledge of how to identify off flavors and aromas, as well as common beer characteristics. I this chapter we will work to develop this knowledge in order to help us identify problems in our beer.

The goal in this first step is not to focus on what you did wrong or come up with solutions. At this stage you want to focus solely on what **is** wrong with the beer. What this means is to be honest about your beer. Take the beer for what it is, and not what you were shooting for, or what you intended. Sometimes you have to let go of your ego and realize that there is the possibility something went wrong. I've seen it time and time again where someone will ask for an opinion on a beer because they either know something is wrong and cannot quite place it, or they want to know what they can do to improve the beer. Then they deny any suggestions others have because they cannot face the fact that something they did could have caused a flaw, or their recipe may need some slight tweaking. The first step is to be open and honest with yourself. If you ask someone else for their opinion, be open to their suggestions. I'm not saying you have to take any single person's opinion as fact, but you must realize that asking someone their opinion opens you up to subjecting your beer to someone else's perceptions and usually that person doesn't have a stake in the beer, so they can tend to be a lot less subjective. So please be respectful of the other person's opinion, because everybody perceives flavors and aromas differently. If you are doing the tasting yourself, try to erase any preconceived notions you have about your own beer and follow the guidelines in the next section to evaluate your beer.

A Quick Overview of Evaluating Beer

The most important thing to know about evaluating your beer is knowing the order of which volatile compounds will dissipate from your beer. The most volatile compounds are the some of the aroma compounds. Have you ever noticed how sometimes there is an aroma in your beer shortly after opening it, that you don't seem to get halfway through your pint? The reason is because some of the aromatics are lost to the air shortly after opening a beer. While at first glance these may not seem like something to worry about, they can play a key role in figuring out what went wrong. Remember, we are not looking at pure enjoyment of the beer, we are troubleshooting the beer. So we will want to gather any possible information we can. The second thing that can change in your beer fairly quickly is the appearance. Mostly we would be looking at the foam, which can change fairly quickly. Next will be flavor, but generally more flavors come to light as the beer warms. So assessing the flavor later can be a benefit, just don't ignore the early sip either. The mouthfeel tends to not change from colder temperatures to warmer, so that is why it is the last individual component we access. Then the last thing we consider is the beer as a whole. You just dissected it by each individual dimension of the beer, now you have to look at how these 4 dimensions coalesce into the entire beer experience. So let's look at each dimension more closely.

Aroma

When assessing aroma, you do not want to fill your glass close to the top. You want to leave plenty of head space to collect all the aromas and you want to be able to stick your nose right down into the glass, a 3 ounce pour into the glass is sufficient for a round of evaluation. The best glasses for a full evaluation will taper in at the top to help trap these aromas. I find a red wine glass is a great all-purpose evaluation glass. Now, I'm not talking about the overall beer experience, in these cases there usually are specific glasses designed for specific beer styles. Using the proper glassware for overall beer enjoyment is very important. But for evaluation purposes only, I like the red wine glass. If you do not have a wine glass, you can use any glass available to you (just make sure it is clear for evaluating appearance), just do not fill the glass near to the top.

You want to be sure you are in a fairly neutral smelling environment. Your home should be just fine as long as you were not frying fish prior to evaluating your beer. If you are not at home, you want to avoid places that have strong overpowering smells. Once you determine your environment and have the proper glassware, you are ready to start evaluation.

Immediately after you pour the beer, take a sniff, and make any mental notes of what aromas you get. Some of these will dissipate almost immediately, but it's important to note them. Do not take large inhaling breaths, but rather short sniffs. This will draw the aroma into the nose but not drag it past all your sensors in your nose and down into the lungs. You want to keep those aromas in your nasal passages. I find it helps to close your eyes so you can focus completely on the aroma. It really helps to write some of the stuff down that you smell, and remember to keep an open mind. Anything you smell can be noted, no matter how weird it may sound to you.

Something to note, is that in longer taste sessions you can burn out your sense of smell. If you find this happening, you do have a reset button. If you smell the back of your hand or your arm, this can help reset your sense of aroma for a few more beers. The way this works, is that your own skin is a very familiar smell to you, and by smelling it, you can essentially recalibrate your sense of smell. Be aware that even this trick will stop working after a while.

Appearance

When evaluating appearance you want to make note of everything visual you see. The color of the beer, the clarity, and the head are obvious things to note. But other aspects you may not at first consider is the foam sticking to the side of the glass, this is called lacing or Belgian lace in some circles. A good lace is a sign of a good clean glass for sure, but it is also the sign of a quality beer. You also want to pay attention to how many bubbles you see rising up though the beer as well as the hue of the beer. The beer may be yellow, but what shade of yellow, is it a clear pale yellow, or is it a clear golden yellow? The hue of the color can add to the appeal of the beer as well.

Flavor

Flavor is the granddaddy element of the beer. While the aroma and the appearance, will influence your perception of the beer's flavor, this is the element that will either turn you completely off from a beer or allow you to accept it. If a beer tastes bad, you probably will not drink it, while if the beer smells bad or even doesn't look right, you probably can endure it. Even some aromas that some consider off-putting (barnyard, goaty, sulfur, etc.) can be acceptable components of aroma in some styles. But if the beer tastes like rotten eggs you probably will not drink it at all.

When evaluating flavor, allow the beer to rest in the mouth for a bit. You don't simply want to drink it, but you want to wash the beer over your entire mouth. That way you can pick up all the flavors residing in the beer. It's important to pay attention to your senses and not discredit any flavor you pick up, even if it doesn't make sense. If a beer has the flavor of toasted marshmallow, that is entirely possible. Don't seek out specific flavors, rather allow them to develop naturally and keep an open mind about what your mouth is telling you.

When you taste hoppy beer, it will be bitter. But it should never be a harsh off-putting bitterness. It can be sharp and bracing, and bitter in the same way a grapefruit is bitter. It should not be bitter like you just inhaled hairspray or some other chemical. It should also be noted that hop bitterness is not hop flavor. Hops bring flavor and bitterness to the table. Hop flavor can range from citrusy, to spicy, to herbal, to woody, and even slightly minty. Hop flavors cover a broad range, and it is beneficial to understand your varieties and what flavors you should expect from that hop type.

In the end, when assessing flavor, I cannot stress enough to just be honest with your beer. Take the flavors for what they are, and don't force it and search for flavors that may not be there. Just because you anticipate there to be a flavor, doesn't mean it will be there; or the other way around.

Mouthfeel

Some people have a hard time with mouthfeel, and in all honesty it is difficult. You can explain an extremely light mouthfeel being close to water, and a very full mouthfeel being closer to that of maple syrup. But since you are describing how the beer feels in your mouth, it can be open to interpretation by each person when you are talking about all the shades between light and full. What is medium to one person, may be a bit light to someone else. But body alone is not the only thing than encompasses mouthfeel. Essentially what you want to focus on in mouthfeel is exactly what the word suggests. How the beer feels inside your mouth. Like I said, this goes beyond just the body (light, medium, and full). The carbonation will play a big role in the mouthfeel. Is the beer flat and lifeless or is it prickly with a highly effervescent carbonation? In some cases, an astringent beer can come across as powdery, which has a powdery feel in the mouth. Diacetyl, while it does have a flavor and aroma, also has a feel in the mouth. It comes across as slick on the tongue. So anything in regards to how the beer physically feels would fall under mouthfeel.

Overall Impression

The Overall Impression brings the 4 other elements together into one unit. Since now you have broken down the aroma, appearance, flavor, and mouthfeel individually, how do they coalesce into one being? Is the balance between the aroma and flavor OK for the beer and/or style? Does the aroma match the flavor? Is the overall balance between these elements what you are shooting for in this beer? That is what you are looking for in the overall impression. Sometimes the individual elements are not that exciting, but once you consider them all as a whole, does the beer work? That is the question.

Most Common Off Flavors and Aromas

**Acetaldehyde:** Apple-like. Usually the aroma and flavor of green apples, but at times can appear to that of other apple aromas or fresh cut pumpkins. In more rare cases, it can appear to be rotten pumpkin. (Jump to Cause) (Jump to Solutions)

**Alcohol:** The aroma or flavor of alcohol, in most cases it would be perceived as overpowering for the style being considered. Often can be tasted as hot, almost like doing a shot of vodka. Sometimes may come across in the aroma as spicy. Higher alcohols can come across like paint thinner or acetone. (jump to cause) (Jump to Solutions)

**Astringency (Tannic):** In the flavor this can come across as puckering, dry, tannic, and tart. The best way to describe it is by chewing on a grape skin or sucking on a tea bag. Sometimes astringency can come across as powdery or metallic. Astringency is dry and puckering, and should not be confused with sour. Astringency is closely related to husky/grainy. (jump to cause) (Jump to Solutions)

**Barnyard:** The aroma of wet horse blanket or damp wet hay. Sometimes also described as "goaty". (jump to cause) (Jump to Solutions)

**Chlorophenolic:** The aroma and/or flavor of plastic, vinyl, or Iodine. (jump to cause) (Jump to Solutions)

**Catty:** The flavor and/or aroma of cat pee, or a litter box. (jump to cause) (Jump to Solutions)

**Cheesy:** The aroma of cheese or sweaty feet. (jump to cause) (jump to solutions)

 **Cider-like** : The flavor and/or aroma of apple cider or apple wine. Sometimes crosses paths with Acetaldehyde. (jump to cause) (Jump to Solutions)

**Diacetyl:** The aroma of butter, turned butter, or butterscotch. In the flavor it can come across as buttery or butterscotch-like. Often with a slickness on the tongue. (jump to cause) (Jump to Solutions)

**DMS (Dimethyl Sulfide):** The aroma of cooked vegetables, most often that of canned or creamed corn. Sometimes it can be perceived as cabbage-like or tomatoes. In rare cases it can come across with an aroma similar to shellfish. (jump to cause) (Jump to Solutions)

**Estery:** Most often described as a fruity taste or aroma. A prime example is the banana-like character in a classic heffeweizen. Sometimes the esters can take the flavor or aroma of other fruits like pears, nectarines, strawberries, apricots, raspberries, or oranges. Other fruit types have been described as well. (jump to cause) (Jump to Solutions)

**Flat:** While not really a flavor or aroma on its own, a flat beer does impact flavor and aroma. It can make a beer seem dead. You will get very little malt and/or hop aroma. Without carbonation pushing these aroma compounds of the beer, some aromas will appear to not be present. A flat beer also impacts mouthfeel and flavor. (jump to cause) (Jump to Solutions)

**Grainy/Husky** : The flavor and/or aroma raw grains. Homebrewers will be especially tuned in to this because it's the smell of your grains after milling. The aromas are often that of dry, pre-mashed grains. In the flavor it will be a bit tannic, closer to the flavor of the grain husk. (jump to cause) **** (Jump to Solutions)

**Grassy:** The aroma of freshly mown grass, sometimes hay. (jump to cause) (Jump to Solutions)

**Medicinal:** The flavors and/or aroma of cough syrup, Band-Aid™ Strips, or spicy cloves. (jump to cause) (Jump to Solutions)

**Metallic:** The Aroma and/or flavor of tin, iron, copper, or other metals. Sometimes described as the taste of pennies and in some cases blood. The flavors are often perceived on the front of the tongue or the back of the throat. (jump to cause) (Jump to Solutions)

**Musty/Moldy:** The aroma, and sometimes flavor of, mold. At times there is an aroma of a musty basement or old wet clothes. (jump to cause) (Jump to Solutions)

**Over Carbonated/Carbonic:** An Over carbonated beer will produce some flavors and sometimes aromas on its own. While it will push out some aromas that you are looking for, with the excess carbon dioxide you can get some CO2 in the nose and it will "smell" like carbon dioxide. Technically CO2 does not have an aroma; it can burn the nose or come across smelling acidic. (jump to cause) (Jump to Solutions)

**Oxidized:** The flavor and aroma of old wet cardboard or newspaper. Sometimes oxidation can come across as slightly fruity or sherry-like. It can also be perceived as that of old and decaying vegetables or fruits. Sometimes oxidized beer can develop an increased harsh bitterness not derived from hops. (jump to cause) (Jump to Solutions)

**Phenolic:** Phenolic is a term used to describe a wide variety of flavors and aromas. Phenolic beers can be spicy and clove-like, smoky, cigar-like, tannic/astringent, medicinal, or even Band-Aid™ like. While some people will simply say a beer is phenolic, they should couple the term with the type of phenol they perceive. The reason is because the different phenolic compounds can mean different issues and are caused by other sources as we will cover in later chapters. So while phenolic is not really a flavor or aroma descriptor, you will find it used as a generic term to cover a wide range of flavors and aromas. (jump to cause) (Jump to Solutions)

**Skunky:** Quite simply and honestly the smell of a skunk. Sometimes warm or oxidized beer is called "skunky" by the general population, but truly skunky beer is simply the aroma of a skunks spray and is the effect of a light-struck beer, not old or warm. (jump to cause) (Jump to Solutions)

**Soapy:** The aroma and/or flavor of soap or detergent. **** (jump to cause) (Jump to Solutions)

**Solvent:** Very similar to hot alcohol, but a bit harsher. There will be a distinct flavor and/or aroma of paint thinner, nail polish remover. Solvent character differs from hot alcohol in that it will generally be harsh, sharp, and in some cases actually cause a burning sensation in your mouth or throat. (jump to cause) (Jump to Solutions)

**Sulfur/Farty:** The smell, and in some cases flavor of, sulfur, rotten eggs, sewage, a baby's poopy diaper, or farts. **** (jump to cause) (Jump to Solutions)

**Sour (acidic):** Vinegary, acidic, tart and acrid. Often found in the flavor, but in extreme cases the sour aroma can be detected. Often, the sour flavor can be tasted on the sides of the tongue and in extreme cases be felt in the jaw. (jump to cause) (Jump to Solutions)

**Sweet:** The flavor and/or aroma of a beer that is cloyingly sweet, or overly sugary. **** (jump to cause) (Jump to Solutions)

**Vegetal:** vegetal flavors are normally that of cooked vegetables. Most commonly that of corn, cabbage, cauliflower, or broccoli. (Jump to cause) (Jump to Solutions)

**Vinegar-like:** See Sour (acidic) (jump to cause) (Jump to Solutions)

**Vinous** : The taste and\or aroma of wine or pressed grapes. **** (jump to cause) (Jump to Solutions)

**Worty:** Tastes or smells like unfermented beer. (jump to cause) (Jump to Solutions)

**Yeasty:** The aroma and sometimes the flavor of yeast, unpitched fresh yeast, or raw bread dough. Sometimes also perceived as sulfur-like. At times it can also be almost "meaty". **** (jump to cause) (Jump to Solutions)

Most Common Non-Fault Beer Flavors

Common Malt Flavors and Aromas

**Biscuity:** The flavor and aroma of biscuits. Often like fresh baked buttermilk biscuits.

**Bready:** This descriptor is fairly straightforward. Most of the time when people are talking about a bready flavor or aroma, it is the smell and flavors of your standard white bread.

**Brown Sugar:** A sweet and brown sugar-like flavor and aroma, sometimes gets mixed in with caramel flavors. But brown sugar tastes like a toned down molasses.

**Caramel** : Caramel can be complex, and the flavors can vary from light and delicate to heavy. The flavor and aroma itself can range from that of typical milk caramel, to that of more of an old world true caramel candy one would make at home. I suggest the best way to become familiar with the flavor and aroma of true caramel; you make a batch at home. (See Appendix III) This will also help you differentiate between caramel and toffee flavors. Sometimes people tend to confuse the two.

**Chocolate** : Often the flavor and aroma of bittersweet, unsweetened, or dark chocolate. At times, you may even experience a milk chocolate flavor and aroma, but most of the time the chocolate flavors are on the dark chocolate side.

**Cracker-like** : Imagine a saltine cracker without the salt. The flavor is light and delicate, with just the slightest amount of toast.

**Crusty** : If you take out an uncut loaf of fresh baked French bread and you smell the crust that is the best way to describe that aroma.

**Coffee** : The coffee flavor and aroma will typically come solely from roasted grain, but some people do make beers with coffee in them. The coffee flavor and aroma can range from very light to almost espresso like.

**Corn** : Not to be confused with DMS, some grains can impart a sweet corn-like aroma, as do beers that use some form of corn as an adjunct. The best way to differentiate between DMS and grain derived corn aroma is that DMS will be more like a canned corn aroma, but corn characteristics that come from grain is closer to the aroma of fresh corn.

**Grainy** : The flavor and aroma of fresh grain. It is often very similar to the cereal grape nuts. If you have ever smelled or tasted your grains, which I'm sure you have at some point, that raw flavor and aroma can transfer over to your beer.

**Honey** : What else can I say? It's the flavor and aroma of honey. Now, not just the sweetness of honey, but honey itself. This is one item that people really should pay attention to, and smell and taste honey. Put the sweetness of it out of your mind, and pay attention to the aroma and the flavor.

**Huskey** : A dry and slightly astringent flavor of grain husks.

**Melanoidin** : Melanoidin flavors and aromas are rich and complex, and actually very hard to describe because it is a flavor and aroma all its own. Munich and Vienna malts are great examples of malts that have a lot of melanoidin flavor and aroma, as well as Melanoidin malt. Melanoidins are formed by the browning action of the beer. If you want to think about what melanoidins flavor is, take some white bread and taste it, then put it in the toaster and toast it. The flavor difference you get is what melanoidin is. I will cover melanoidins a bit more in depth in part 4.

**Molasses** : The flavor and aroma of molasses. It can range from mild though blackstrap. Molasses is a flavor all on its own, if you are unfamiliar with it, you really should pick some up for training your palate.

**Nutty** : Often this is the smell and flavor of almonds, but this descriptor can take the form of any nut. Chocolate malt in small amounts can lend nuttiness to the beer as well as some medium range toasted malts.

**Raisin** : Believe it or not, you can get this flavor from malt. Special B is a good example of malt that can help bring you a raisin-like flavor to the beer.

**Roast** : The generic flavor and aroma of roasted grain. It will have a burnt and acrid flavor and aroma. In most cases, small doses of that flavor/aroma is OK in many dark styles, but when over done it can be very off putting.

**Toast** : See Melanoidin.

**Toffee** : Toffee will often have a brown sugar-like and buttery flavor. It is similar to caramel but a little softer.

**Treacle** : Treacle is syrup made during the sugar refinement process. You have 2 types of treacle, one lighter shade called golden syrup and one darker shade called black treacle. It is a slightly bitter and very distinctive type of syrup. This is also a flavor to become familiar with by buying some in the store. Some of your darker crystal/caramel malts can impart a treacle-like flavor into a beer.

Common Hop Flavors and Aromas

This is where it can get a bit tricky. Some off-flavors that are faults can also be a characteristic of hops. So it's important to know the varieties of hops used in a beer. For an example, if an American IPA is brewed with Simcoe, it may have a catty aroma because that is a character of the hop. But if you get that same aroma in a Bock beer, it would be a fault. So knowing your ingredients and process is vital to an accurate assessment.

**Catty:** Some hop varieties, like Simcoe for example can have a catty aroma and flavor. Some describe the aroma of that of cat urine.

**Cheesy:** Typically you will find this cheesy aroma in aged hops and is a characteristic of some Belgian styles where this is acceptable (lambics for example). Most other styles the aroma of cheese is not acceptable.

**Citrusy:** In hop flavor and aroma, you can get a wide variety of citrus fruits from several American varieties of hops. The citrus can be in both flavor and aroma. You could expect to find sweet and bitter orange flavors (common), grapefruit (most common), lemon (uncommon), lime (rare), and tangerine (rare).

**Fruity:** Very similar in character to the citrus hops, but some hop varieties can impart a peach, pineapple, nectarines, and apricot flavor and/or aroma. Generally these flavors and aromas are fairly rare but it is not unheard of. Amarillo for example, can give the impression of pineapple or nectarines in lightly hoped beers.

**Grassy:** Simply put, it is the aroma of freshly mown grass or fresh hay. Sometimes you will get this more often in fresh hop beers and sometimes in dry hopped beers.

**Herbal:** This is another broad spectrum of flavors and aroma from hops. The aroma can be perceived as just about any herb you have come across. Commonly you will get the perception of oregano, rosemary, mint, or thyme. Parsley is another common one. Many times people just use the descriptor of "herbal hops" because sometimes it can be hard to nail down one specific aroma. The reason is that these aromas are often a muddling of a combination of herbal-like aromas.

**Minty:** This is technically the same as herbal, but mint is a very distinctive aroma and flavor so I gave it its own line. Perle hops tend to have this minty flavor and aroma.

**Piney:** This is another common characteristic of several American hop varieties. Piney hops will have the aroma, and flavor, of fresh pine. For a good exposure to pine flavor, brew yourself up a batch of spruce tea if you have access to spruce tips.

**Resinous:** Resinous is both a flavor and a mouthfeel. Resinous hops will typically be very similar to piney hops, but actually have the aroma of the sap, and the flavor will be pronounced and bracing and feel like it sticks in your mouth. If you have ever heard anyone use the term "sticky hops" they are referring to this sensation.

**Spicy:** The flavor and aroma of spicy hops varieties is not the type of spicy from hot peppers, but that of spices. Sometimes the flavors and aromas will be slightly clove-like, that of peppercorns, or like mulled spices. Sometimes it can even be a bit like fresh ginger or even a spice blend from spice cake. When someone says they taste or smell spicy hops that is the sort of spicy they are referring to.

**Soapy:** If you have ever had your mouth washed out with soap, then you will get what this flavor and aroma can be all about. **** While it's not common for some hops to have a soapy flavor, it does happen from time to time with some American hops, from personal experience it seems to come with hop blends of resinous hops and floral hops sometimes. ****

**Woody (earthy):** The aroma and sometimes flavor of various woods. Sometimes this is also described as earthy. A prime example of this flavor would come from Northern Brewer hops.

Common Yeast Flavors and Aromas

Again, some off-flavors that are faults can also be a characteristic of yeast. For example, if you are making an American Pale Ale, you want the yeast profile to be clean, so if you are getting a phenolic clove-like flavor or aroma from the yeast, it will be a fault in an American Pale Ale, but in a German Heffeweizen, it is expected. So like I said earlier, knowing your ingredients and process is vital to an accurate assessment.

**"Belgian":** While not an official flavor or aroma descriptor, **** you will often see or hear this term. It doesn't really describe anything and is often just a generic term used when someone doesn't know how to describe the yeast flavor and aroma. While it's true, that Belgian style yeast tends to have a stereotypical aroma, each strain is a bit different. Personally, I have found the term that people refer to as "Belgian" is usually a combination of spicy and estery. So it's a bit fruity and a bit spicy, like baking spices.

**Estery:** While a flaw in many styles, some styles require there to be some fruity esters, or at least are acceptable in low levels. They are usually most prominent in the aroma, but in higher levels can come through in the flavor. Estery beers will generally have some degree of fruitiness.

**Meaty:** While not desirable, some yeast flavors can come across as meaty. It will give you the flavor and aroma of raw or sometimes even spoiled meat. This is always a flaw.

**Phenolic:** As covered in the flaws sections, phenols cover a wide range of flavors and aromas. Some are desirable in some styles, and others are almost always a flaw. Phenolics in beers can come across in a wide spectrum of flavors and aromas. Some examples are smoky, spicy (cloves), medicinal, tannic or astringent. While technically phenolic is not really a flavor or aroma descriptor, it's more of a cause, many people will say a beer is "phenolic" so it is notable to mention it so you can get an idea of what they may be saying.

**Spicy:** Without sounding too redundant, yeast can often contribute to spicy flavors and aromas in beer. Most notable is the clove-like flavor and aroma often produced by Belgian strains and German Heffeweizen strains of yeast. But there are other more subtle spicy flavors and aromas that can be produced by yeast. Most often they come across as cooking spices like vanilla, cumin, all-spice, and other spices similar to these.

**Sulfur:** The aroma of eggs, or rotten eggs. Sometimes also referred to as "farty". It is a common by product of some lager strains.

Common Water Flavors and Aromas

Water itself is usually a fairly neutral component of beer in regards to flavor. There are some flavor and aroma components that water contributes to the beer based on the water chemistry of the source and how it reacts to the brewing process and other ingredients. There are hundreds of variables; I will narrow it down to the most common 5.

**Bitter (harsh):** High sulfate levels in your water can contribute to some very harsh and unpleasant bitterness. In lower hopped beers, it can give the perception of a higher bitterness than what you are shooting for.

**Medicinal:** The chlorine level in the beer can lead to chlorophelnoic, or medicinal flavors and aromas. These tend to be unpleasant and are more common in unfiltered municipal water sources. ****

**Metallic:** This one is pretty self-explanatory. If your water has unusually high concentrations of iron, copper, or other metals; it can lead to metallic or tin-like aromas and flavors in the beer as well. ****

**Salty:** Some homes use a water softener that will add extra sodium to the water used in your beer. This can lead to a salty flavor in some delicate beer styles.

**Sulfur:** This is most common in rural water supplies. A high iron reading in your water can lead to a sulfur-like smell because of the breakdown of irons by microbes in the water. In short, if you water smells like sulfur or rotten eggs, that aroma will carry over into your beer.

Training Your Senses

Now that we have a general understanding of the evaluation process and we have a broad understanding of common flavors, aromas, and faults to find in beer. We need to be able to develop the skills to be able to make the connections between our brains and our sense of taste, smell, sight, and feel. While this process is the most commonly skipped, I feel it is essential to developing a solid accurate palate. While some flavors like chocolate are easy to assess, differentiating between caramel and toffee notes can take some practice. Because the two are not the same and what may be acceptable in one style is not always acceptable in another style, it is important to understand the difference. Sometimes the only way to know the difference is to compare attributes side by side, and whenever possible add these attributes to a beer. You can do this a couple of different ways; my favorite is by doing what is called a Doctored Beer Lab. This is where you start out with a relatively neutral beer, like your standard American Light Lagers and you purposely add contaminants to the beer. You choose these American Light lagers because these are the beers where any minor change will be fairly easy to detect. As you progress, you can add these contaminants to other beer styles which will be a slightly harder to detect the flaws because there is more flavor and aroma for these faults to hide behind or meld with. There are commercial doctored beer kits which can be purchased online. While the dosages are premeasured, they tend to be a bit more expensive. You can easily make your own doctored up beers at home with household ingredients. I will provide you with some guidelines to doctoring beer, which can easily be found online.

The chart below can be used to help train for the perception of the listed flaws/attributes for beer flavor and aroma. You can decrease the amounts as you become accustom to the flavor/aroma. _In addition, you can use any edible product to doctor beers. So you can add vanilla extract to train for vanilla character, anise for black licorice, cherry juice for cherry, and so on. Use your imagination, the possibilities are almost endless, so as long as it is edible, you can use it for beer. Using chemical enhancers should only be done with the proper kits and instruments for adding the exact proper amounts to the samples._

Flavor | Additive/Method (Per 12oz of beer) | Quantity

---|---|---

Sour/Acidic | USP lactic acid* | 0.4 ml (use 1/3 tsp of the following solution: 1/8 teaspoon lactic acid plus 3/8 teaspoon distilled water)

DMS | Juice from Can of Corn** | 2 Tbsp of juice from a can of corn

Sour/Acidic | White wine vinegar** | 3/4 tsp.

Bitterness | iso-hop extract* or Homemade   
hop extract from Vodka soak (See Appendix I)  | 1 or 2 drops, to taste

Sweetness | sucrose (table sugar)** | 1/4 tsp. dissolved in 1/2 tsp water

Astringency | Grape Tannin* | 2 tsp. of solution of 1/8 tsp. tannin dissolved in 5 tbs. water

Phenolic | Chloraseptic** | 0.4 ml (1/3. tsp of solution of 1/8 tsp. Chloroseptic plus 3/8 tsp. distilled water)

Clove like | Clove solution** | Make solution of 8 cloves soaked in 3 oz. of beer and add liquid to taste (about 4 tsp)

Sulfitic | Potassium metabisulfite* | Make solution of one tablet dissolved in 3 oz. of beer and add to taste (about 1/2 tsp.)

Alcoholic | Ethanol (everclear)** | 2 tsp. (increases alcohol by 2.7%). 3 tsp. vodka may also be used

Sherry-like | Dry sherry** | 3/4 tsp.

Nutty | Almond extract** | 0.1 ml (1/8 tsp of solution consisting of 1/8 tsp. almond extract plus 5/8 tsp. distilled water)

Papery/Stale | N/A | Open bottles to air, reseal, and keep at 100 F or warmer for several days. I find it best to pour the beer from one bottle to a new sanitized bottle then recap.

Winey | White wine** | 2 tbs.

Diacetyl | Butter extract** | 2-5 drops (Depending on intensity desired)

Estery | Banana extract or other fruit extracts** | 2-7 drops (Depending on intensity desired)

Lightstruck | N/A | Expose commercial beer in clear bottles to direct sunlight for 1-3 days.

Malt Flavors/Aromas | Use Desired Malt*** | 1) Create wort with no hops and ferment with a neutral yeast strain, and evaluate. B) Create a single malt single hop beer and change only the malt through a series. Note the differences the changes in malt make.

Hop Flavors/Aromas Aromas | Use Desired Hops*** | Create a beer using only pale ale malt, neutral ale yeast, and any single hop variety. Keep the same grains and yeast, but change the hop from batch to batch to learn the hop aromas and flavors.

Yeast Flavors/Aromas | Use Desired Yeast Strain*** | Create a beer with a fairly malt neutral and low hopped beer. Changing only the yeast strain from batch to batch.

*= Can be purchased at most Homebrew Supply Shops  
**= Can be purchased at the local grocery store  
***=Does not have to be full 5 gallon batches. A perfect lab for small batch brews (1-3 gallons)

Another way to work to train your palate is to simply pay attention. When you eat or drink, be mindful of what you are eating or drinking. Make mental notes about what you are eating, how does it smell? How does it taste? If you can, close your eyes and examine through taste and smell how certain foods or ingredients are perceived by your body. While this may not necessarily be as accurate for things like off-flavors, this will help you build connections to flavor and aroma descriptors. While this may at first sound overly simple, most of the time we enjoy our food or drink but don't really pay attention to the aromas and flavors closely. This is what I am talking about, awareness of flavors and aromas will help you develop those connections. As you will have noticed in previous sections, many of the flavor descriptors are similar to common everyday foods. Eating these foods and paying close attention to details we often breeze over will help tremendously. For example, next time you buy some good crusty bread, like fresh French bread, crack it open and smell the bread itself, then smell the crust. You will notice that there is a difference. The aroma of the bread is normally what people will refer to as "Bready" and the aroma you get in the crust will be what some people describe as "crusty bread" or Bread Crust". Both are bready notes per say, but if you can distinguish between the two; you will be able to give a much more accurate assessment. So take a look at the flavor and aroma descriptors and seek out these items, and pay close attention to the flavor and aroma. I can't stress that enough.

Getting Acquainted With the Guidelines

Style Guidelines are important, like or not. Some people claim to not brew to any specific style, and that is fine, but whether they like it or not, chances are their beer falls somewhere within the guidelines of some specific beer style. The purpose of the style guidelines is to provide a target range for a beers flavor, aroma, appearance, and mouthfeel and is indispensable when troubleshooting your beer. This framework provides a set of rules of which you can more accurately gauge your success in brewing your beer. So if you don't want to restrict yourself to fitting within a guideline that is fine. But think of it like this, you have a bow and arrow and want to find out how good of a shot you are. So you place a target in front of you and you aim for the bullseye. How close you get to the bullseye determines your success in this round of shooting. However, if you have no target and you just draw back the bow and fire off your arrow into the air. How do you know how close to the mark you were? Now the target does not necessarily have to a formalized guideline, but at the very least you need to pre-define what you want your beer to taste like, what it should smell like, what it should look like, and how it should feel. Without that idea of what it was supposed to be, you will have a hard time getting a handle on your brewing process and will have a difficult time with consistency in your beer.

There is more than once source for guidelines. The BJCP (www.bjcp.org) is probably the most well-known to homebrewers. The BJCP guidelines are the standard set of guidelines used in almost all homebrew competitions. There are also guidelines provided by the Brewers Association (www.brewersassociation.org). The Brewers Association guidelines are well known for being used in the Great American Beer Festival, which is geared more towards professional breweries. Both guidelines are very similar, almost identical in a majority of styles. But I personally find the BJCP guidelines a bit more in depth than the Brewer's Association guidelines. You can use whichever guidelines you prefer. Below I have provided an example of the BJCP guideline's version for a Weissbier beer and the Brewer's Association's guidelines for the same style. You compare the verbiage and decide which type of guideline fits your style. Again, a good guideline should provide you with insight into what the beer should smell like, what it should taste like, what it should look like, and how it should feel. Technical data is OK as well, like what the gravity or IBU's should be, but strictly for a flavor and aroma guide, that data doesn't really matter quite as much. You will also sometimes find traditional ingredients or brewing processes that are recommended for a specific style. While this may not be as critical for the evaluation stage, it can help you in accurately re-creating a historical style or ensure that the beer you made meets the criteria of a given style. But again, for our purpose here we are more concerned with the flavor, aroma, appearance, and mouthfeel data in the guidelines. Below are the examples.

## The BJCP: Category 15A. Weizen/Weissbier

 **Aroma:** Moderate to strong phenols (usually clove) and fruity esters (usually banana). The balance and intensity of the phenol and ester components can vary but the best examples are reasonably balanced and fairly prominent. Noble hop character ranges from low to none. A light to moderate wheat aroma (which might be perceived as bready or grainy) may be present but other malt characteristics should not. No diacetyl or DMS. Optional, but acceptable, aromatics can include a light, citrusy tartness, a light to moderate vanilla character, and/or a low bubblegum aroma. None of these optional characteristics should be high or dominant, but often can add to the complexity and balance.

 **Appearance:** Pale straw to very dark gold in color. A very thick, moussy, long-lasting white head is characteristic. The high protein content of wheat impairs clarity in an unfiltered beer, although the level of haze is somewhat variable. A beer "mit hefe" is also cloudy from suspended yeast sediment (which should be roused before drinking). The filtered Krystal version has no yeast and is brilliantly clear.

**Flavor:** Low to moderately strong banana and clove flavor. The balance and intensity of the phenol and ester components can vary but the best examples are reasonably balanced and fairly prominent. Optionally, a very light to moderate vanilla character and/or low bubblegum notes can accentuate the banana flavor, sweetness and roundness; neither should be dominant if present. The soft, somewhat bready or grainy flavor of wheat is complementary, as is a slightly sweet Pils malt character. Hop flavor is very low to none, and hop bitterness is very low to moderately low. A tart, citrusy character from yeast and high carbonation is often present. Well rounded, flavorful palate with a relatively dry finish. No diacetyl or DMS.

 **Mouthfeel:** Medium-light to medium body; never heavy. Suspended yeast may increase the perception of body. The texture of wheat imparts the sensation of a fluffy, creamy fullness that may progress to a light, spritzy finish aided by high carbonation. Always effervescent.

 **Overall Impression:** A pale, spicy, fruity, refreshing wheat-based ale.

**History:** A traditional wheat-based ale originating in Southern Germany that is a specialty for summer consumption, but generally produced year-round.

 **Comments:** These are refreshing, fast-maturing beers that are lightly hopped and show a unique banana-and-clove yeast character. These beers often don't age well and are best enjoyed while young and fresh. The version "mit hefe" is served with yeast sediment stirred in; the krystal version is filtered for excellent clarity. Bottles with yeast are traditionally swirled or gently rolled prior to serving. The character of a krystal weizen is generally fruitier and less phenolic than that of the hefe-weizen.

 **Ingredients:** By German law, at least 50% of the grist must be malted wheat, although some versions use up to 70%; the remainder is Pilsner malt. A traditional decoction mash gives the appropriate body without cloying sweetness. Weizen ale yeasts produce the typical spicy and fruity character, although extreme fermentation temperatures can affect the balance and produce off-flavors. A small amount of noble hops are used only for bitterness.

 **Vital Statistics:** OG: 1.044 – 1.052

IBUs: 8 – 15 FG: 1.010 – 1.014

SRM: 2 – 8 ABV: 4.3 – 5.6%

 **Commercial Examples:** Weihenstephaner Hefeweissbier, Schneider Weisse Weizenhell, Paulaner Hefe-Weizen, Hacker-Pschorr Weisse, Plank Bavarian Hefeweizen, Ayinger Bräu Weisse, Ettaler Weissbier Hell, Franziskaner Hefe-Weisse, Andechser Weissbier Hefetrüb, Kapuziner Weissbier, Erdinger Weissbier, Penn Weizen, Barrelhouse Hocking Hills HefeWeizen, Eisenbahn Weizenbier

---

Brewer's Association: South German-Style Hefeweizen/Hefeweissbier

The aroma and flavor of a Weissbier with yeast is decidedly fruity and phenolic. The phenolic characteristics are often described as clove- or nutmeg-like and can be smoky or even vanilla-like. Banana-like esters should be present at low to medium-high levels. These beers are made with at least 50 percent malted wheat, and hop rates are quite low. Hop flavor and aroma are absent or present

at very low levels. Weissbier is well attenuated and very highly carbonated and a medium to full bodied beer. The color is very pale to pale amber. Because yeast is present, the beer will have yeast flavor and a characteristically fuller mouthfeel and may be appropriately very cloudy. No diacetyl should be perceived. _(Brewer may indicate a desire that the yeast be either poured or not_ _poured when the beer is served.)_

**Original Gravity (ºPlato)** 1.047-1.056 (11.8-14 ºPlato) ● **Apparent Extract/Final Gravity (ºPlato)** 1.008-1.016 (2-4 ºPlato) ●

 **Alcohol by Weight (Volume)** 3.9-4.4% (4.9-5.5%) ● **Bitterness (IBU)** 10-15 ● **Color SRM (EBC)** 3-9 (6-18 EBC)

---

So as you can see, the BJCP guidelines go a bit more in depth, and the Brewer's Association leaves a bit more open to interpretation and provides a very loose framework for what the beer should be like. Both guidelines are just fine, and it's up to you which you prefer. At the time of writing this, there are 140 different beer styles listed in the Brewer's Association guidelines and the BJCP has 23 major beer styles and 80 subtypes (not including mead and cider categories). So there is a lot of ground to cover if you are not familiar with beer styles at all.

Let's say you don't want to use the style guidelines set forth by a governing organization. You want to be a rogue brewer and define your own path. The very least you should do is define what you want your beer to smell like. What goals are you shooting for as far as the malt profile, the hop aroma, and the depth of hop aroma? What flaws (if any) would you find acceptable, and the impression of the aroma. Do the same for the flavor. Then gauge what color range are you shooting for. Are you shooting for a pale yellow beer, an amber beer, brown, or nearly black? How much mouthfeel are looking for? Do you want it thin or full bodied? Do this when you formulate your recipe. Then after the beer is brewed, you can determine how close to your personal mark you have achieved. Without this framework, you're just flinging your arrows around without any rhyme or reason. What fun is that?

Putting It All Together

So now that we have all the basic knowledge we need to evaluate the beer, what next? Well, at this point you know how to evaluate a beer by aroma, taste, and feel. You have a general understanding of the most common flavors and aromas in beer in regards to malt, yeast, hops, and water. You have an idea of some common flaws. You also have knowledge about how to use style guidelines as a target for your beer evaluation round. You put all these components together to come up with what you beer is right now, and honestly that part is harder than acquiring this basic knowledge. The hardest part is letting go of "what you were shooting for" or what the beer was supposed to taste like and really taking a look at the beer in an open minded and non-judgmental way. That is the hardest part because we always tend to go one way or the other. We either tend to be our own worst critic, or we fail to acknowledge the flaws or mistakes in our beer because there is no way we made a mistake that would make it taste like this. Judging your own beer openly and non-objectively is a lot more difficult than it seems. This is why many people send beers off to competition. Competitions tend to be fairly inexpensive, and you are getting blind feedback from someone who doesn't know your process or what ingredients you used. They don't have a stake in telling you that you did a great job. But don't get me wrong, evaluating beer is a very important part of the brewing process. So use the information in the chapter and take your beer for what it is, not for what you wanted it to be or what it should have been. Be honest with the beer.

The best way, in my opinion, to evaluate your own beer is to sit down with a glass of it and write down what you smell, what you taste, and do so before you read the guidelines or the guidelines you wrote down for what you wanted the beer to be. Write down how the beer smells and be as accurate as you can with the descriptors. Does it smell bready, caramel-like, or dry and grainy? Is the hop aroma pronounced or subtle, is it bright? What do the hops smell like? Are they citrusy, spicy, piney, or grassy? Are there any other aromas, like that of corn or vegetables? Do the same for the flavor. How does the beer look? Is it clear, semi-clear, or cloudy? Does it have a good head? Does the head last a long time? Does the beer feel thin and watery in your mouth, or does it have some body to it? Do you smell or taste any alcohol? Do you detect any alcohol in the flavor or aroma? All of these things will help you later. Then once you have your written description down, go back to the guideline you have chosen and see how well the beer matches up with what you wrote. Once you do that, you can begin to see where you may have been led astray, and use the next step, establishing a theory, to begin to figure out how to fix it.

Step 2: Establishing a Theory

So now that we know what our beer tastes like, what it smells like, and how it feels. We also know the target that we were shooting for, so what comes next? Well, if you were exactly on target for what you were shooting for. Nothing, you are done! Good Job! But if you detected a flaw or even if the beer was not exactly what you were hoping for. We need to establish a theory of what went wrong so that we can fix it. In order to do this, we need to understand what process or ingredient failures can create certain results. Now the combinations of problems that can be caused are endless. But this chapter will focus on the most common causes of common faults and we will go from there. To establish our theory, we will follow 4 simple rules.

-What are the possible causes?

-Could you reliably and consistently predict or determine the same result?

-What causes are the least likely?

-What causes are most likely?

Most Common Causes Off-Flavors and Aromas

While there can be multiple causes for off flavors and aromas, I will provide the most common causes. This is no way every single potential issue, but these causes will cover a good 90% or better of the potential issues you may run across.

**Acetaldehyde:** Most commonly the cause of Acetaldehyde is that the beer is too young and has been pulled off the yeast too quickly. (Jump to Solutions)

**Alcohol:** There can be a few causes of beer that is higher in alcohol than you wish. If the beer is too high in alcohol the there are multiple common causes. One would be that the beers gravity was higher than you were expecting, therefore producing more alcohol in the finished beer.  
The second cause would be more fermentable wort than you were anticipating.   
Third would be that the beer fermented at a high temperature for the yeast strain. . (Jump to Solutions)

**Astringency (Tannic):** One of the top contributors to astringency in beer is tannins. Tannins are a type of phenol called polyphenols. Tannins are found naturally in the husks of the grain and can be released from excessive steeping of the grain, over crushing the grain, excessively hot water while sparging, and most commonly if the pH of your mash exceeds 5.6.   
Hops can also contribute astringent properties if the pH of your beer is above 5.6 as well. The polyphenols in the hops are not soluble in the beer unless your pH is below that magic 5.6 mark (ideally 5.3-5.4), so over hopping of a beer can lead to some astringency. In some cases the hot break proteins, if left in your fermentor can come across as astringent. As do some wild yeast/bacterial infection.  (Jump to Solutions)

**Barnyard:** In some cases, like in wild fermented beer, this attribute is acceptable. But in a wide range of beers, a barnyard-like or horse blanket aroma is a sure sign of unwanted bacterial infection. Most commonly, this would be Brettanomyces. (Jump to Solutions)

**Chlorophenolic (see also Medicinal):** This is a type of phenol, but still worth separating from regular phenols. The main cause of this particular flaw is chlorine or chloramine in your water or residue left behind by other cleansers. Even the smallest amount of chlorine in your beer can impart some medicinal flavors. I am very strongly against using bleach as a sanitizer. For one, you have rinse it which negates the sanitation process to begin with, second is even just a few parts per billion of chlorine can lead to this problem. While chlorine or chloramine is the number one cause, some wild yeast and bacteria can also cause this unpleasant flavor and aroma. (Jump to Solutions)

**Catty:** Most commonly, you will get catty aroma from certain types of hops, Simcoe in particular but it can also be a characteristic of Chinook, Summit, Cluster, and Newport hops. Some people love the flavor and aroma of Simcoe and some people find it really off-putting. Sometimes an old hoppy IPA can become catty with age as well. There are some people who may combine the term "catty" with "skunky" as well. I suspect because in some regions a skunk is called a polecat. (Jump to Solutions)

**Cheesy:** As hops age, the alpha acids degrade over time producing something called isovaleric acid. This same fatty acid compound is commonly found in stinky cheeses. (jump to solutions)

**Cider-like** : Cider flavors are often associated with the use of too much corn sugar in a recipe, but there has been some debate recently to whether or not It's really the cause. It is something to consider. Another cause is old extract. So if you are an extract brewer or a partial mash brewer, the age of the extract could be a factor. This is also the reason for the debate because generally the cider flavor coming from the use of corn sugar originated during the era when you would get a can of extract from a homebrew shop which in most cases was exported from Europe, and then supplement the recipe with a lot of sugar. The speculation is that the cider flavor may actually more attributed to old extract than to sugar itself. Either way, it's something to consider. Other causes can be from warmer fermentation temperature (esters) and in some cases can be a sure sign of an acetobacter infection. (Jump to Solutions)

**Diacetyl:** Diacetyl is a natural byproduct of fermentation by almost all beer yeast strains. Generally the diacetyl is reabsorbed by the yeast cells before dropping out. There are a few causes that would prevent the yeast from reabsorbing the diacetyl. These would be racking the beer to the bottle or keg to early, poor fermentation health which could lead to the yeast dropping out early or high fluctuations in fermentation temperature which could cause the yeast to flocculate. In lagers, Diacetyl is absorbed more slowly due to the low fermentation temperature. (Jump to Solutions)

**DMS (Dimethyl Sulfide):** DMS is another natural product of the brewing process. DMS is formed when the compound S-methyl-methionine (SMM for short) is reducing because of heating. SMM is produced inside the grain during the malting process, and is slowly reduced anytime when the wort is heated. What is left behind as SMM is reduced is DMS, which in turn is also driven off during the boil. This is by far the most common cause of DMS, but DMS can also be produced by bacterial infections. In the case of the bacterial production of DMS, you start leaving the cooked corn aroma and approach the vegetal or rotten vegetable aromas. But they are both the DMS compound at heart. (Jump to Solutions)

**Estery:** Esters are a natural byproduct of fermentation. The type of esters and the levels produced are dependent on the strain of yeast and the temperature that the beer was fermented. However, high levels of fruity esters can be a sign of an overly stressed fermentation. This stress can be caused by too low of oxygen levels, pitching too little yeast, and excessively high fermentation temperature. (Jump to Solutions)

**Grassy:** Fresh hops and some hop varieties will give you the grassy aromatic, which seems a bit obvious. However, poorly stored grains can develop mold or bacterial colonies on them that will also produce grassy notes in the finished beer. (Jump to Solutions)

**Grainy/Husky** : Grainy and husky can be a sign of astringency problems, as well as an attribute of the grain itself. I usually like to look at it as if the husky or grainy aroma/flavor is pleasant or unpleasant. If it's pleasant it could be grain derived and something you want. If the grainy or husky flavor/aroma is unpleasant, it could be from over crushing the grain or not paying attention to proper mashing processes. There are some toasted grains which will impart a grainy aroma to the beer as well, so be aware of the grains you use. If you have read my book on home roasting malts, you will also know that if you don't allow your grains to mellow for a minimum of 1 week (2-3 weeks optimal), you can get some harsh grainy notes as well. (Jump to Solutions)

**Medicinal (see also Chlorophenolic):** A phenol of some sort is the cause of medicinal flavors/aromas nearly 100% of the time. These phenols can be produced by poor mashing practices, having a mash pH that is way off base for example. Residual cleaners and sanitizers that are not no-rinse can also lead to this flaw. A good example is people who use chlorine bleach to sanitize. Even the smallest amount of chlorine in your beer can impart some medicinal flavors. I am very strongly against using bleach as a sanitizer. For one, you have rinse it which negates the sanitation process to begin with, second is even just a few parts per billion of chlorine can lead to this off-flavor. (Jump to Solutions)

**Metallic:** The most common cause I have found is if you are using abrasives on your metal equipment, then brew without passivation of the stainless steel. A good example of what I am talking about is if you clean your kegs or kettle with Ajax instead of Barkeepers friend to scrub your equipment. However you can get metallic flavors from water that has high iron content or using sub-par aluminum or other metals in your brewing process. In rare cases, musty grains can come across as slightly metallic in the finished beer as well. (Jump to Solutions)

**Musty/Moldy:** Several varieties of mold and mildew can survive and thrive on beer. If the flavor is distinctly moldy, the chances are fairly solid that you have a mold contamination. Mold can also grow on improperly stored grains and impart that flavor/aroma to the finished beer as well. If the aroma is musty, there is a good chance it is also from poorly stored grains; however extended aging in some cases can lead to a musty aroma as well. This is most common in poorly stored corked beers. For example if you store a corked beer for a long period of time in a musty damp basement, that can make its way into the beer. (Jump to Solutions)

**Over Carbonated/Carbonic:** For bottled beer the most common causes are that you used too much priming sugar or the beer was not done fermenting when you bottled it. For kegging, the causes can be the same, except now you can adjust the amount of pressure and you have the glorious pressure release valve to release excess pressure. The temperature of the beer as you carbonate it can make a difference too. The colder the beer, the more CO2 you can dissolve into solution. In some cases, wild yeast and/or bacterial infections can ferment the more complex sugar chains and not only dry out the beer, but also over carbonate it as well. (Jump to Solutions)

**Oxidized:** Exposure to any amount of oxygen and warmer temperatures will quickly oxidize the beer. This oxidation can occur during bottling/Kegging or be caused by a small amount of oxygen trapped in the bottle or keg. There is some debate over the aeration of hot wort causing something called hot-side aeration, but there have been studies that show it to not be much of a concern. Which makes sense to me since any dissolved oxygen prior to fermentation would be used by the yeast. I don't see how highly oxygenated wort when warm would make it any more highly oxygenated post fermentation than if I run my pure oxygen through after the boil. But since it is a concern for some, there may be something to it to consider if oxidized off-flavors are a problem for you and you ruled out all other post fermentation causes. **** (Jump to Solutions)

**Phenolic:** This would be the general catch-all group for phenols in beer, be it good or bad. It can be the result of unnatural chemicals in the beer as in the case of chlorine or other cleaning solutions and/or leaching of flavors from plastic hoses or gaskets. Some malt, like peated malt, contains high levels of phenols naturally. These tend to be more along the smoky side, and are the main reason you need to be fairly restrained in your use of peated and smoked malts. Phenols are also a natural byproduct of yeast fermentation in some strains of yeast, and are in some ways unavoidable. For example Bavarian Heffeweizen yeast. These yeast strains have enzymes that are not present in other strains, like California Ale yeast. These enzymes work to covert the phenolic acids in the malt, which is normally undetectable by humans, into aromatic phenols through a decarboxylation reaction during fermentation, in almost all cases where these sort of "clove-like" phenols are detected; it is desired because you chose that type of yeast to impart that sort of flavor/aroma. If unwanted clove-like phenols are present, that indicates a wild yeast or bacterial infection. Some phenols are produced during the mashing and sparging process. This type of phenol is covered in the astringent/tannic section, but is worth mentioning here because although it has its own description, the polyphenols produced by the mashing and sparging process are technically phenols even though we tend to call them tannins. (Jump to Solutions)

**Skunky:** Exposure to sunlight (UV light to be exact) causes a chemical reaction in the isomerized hops which releases a chemical called isopentyl mercaptan, which is the same compound found in the skunks stink glands. So yes, a beer that is really skunked literally has the same smelly compound a skunk sprays. (Jump to Solutions)

**Soapy:** Over Exposure to fatty acids in the primary can cause soapy flavors as those acids break down. These fatty acids are formed during fermentation, and at moderate levels are completely normal and not harmful to your beer. In high levels, these acids can form the soapy flavor and aroma you may not want. Also, some newer hop varieties can also give a soapy flavor impression. **** (Jump to Solutions)

**Solvent:** Solvent flavors and aroma are very similar to alcoholic, except these are a lot harsher. This is more along the lines of acetone or nail polish remover. These are very commonly caused by high fermentation temperatures combined with oxygen. You will most commonly see this when you over-aerate your wort and ferment at temperatures above 75° F (for average yeast strains. Some yeast strains can easily handle this temperature). In some more rare cases, you can run across this if you are not careful about the type of plastic your beer comes in contact with. Non-food grade plastics and PVC piping can have undesirable chemicals leech into the finished beer. (Jump to Solutions)

**Sulfur/Farty** : I know the term "farty" is not a professional term, but you may hear that term used as a descriptor from time to time. Sulfur compounds are a natural by-product from the yeast during fermentation. Lager yeast in particular is known to throw off a high amount of hydrogen sulfide, which is what you smell. ** **(Jump to Solutions)

**Sour (acidic):** If you are looking for a sour beer, you probably added some specific yeast and bacterial cultures to your beer to achieve that flavor. If you are finding your beer to be sour, it is almost always an unwanted infection. This infection can be caused by a multitude of factors. If you have produced a sour beer in the past in the same equipment, it could be that your sanitation processes didn't fully kill any old yeast/bacterial strains. Scratched equipment could be to blame. If you have never made a sour beer in the past, it is most likely a wild contamination. This can happen from any naturally occurring yeast or bacteria in the air that may have settled on your beer or equipment during transfer. A long extended mash can also turn sour because grain naturally has lactobacillus in the husks. (Jump to Solutions)

**Sweet** : Since beer is made from converting starches in the grain to sugar, you will always have some degree of sweetness. However if the beer is overly sweet or worty (see below), there may be something going on. If you are an extract brewer, you will tend to naturally have a higher finishing gravity. But it should never be cloyingly sweet either. In both extract and all-grain cases, where the beer is too sweet, it is most likely caused by the yeast stopping fermentation too soon. There are many factors that can cause the yeast to stop fermenting, and we will cover those later. Another cause, mostly of concern to the all-grain crowd is your mash temperature. Too high of a mash temperature will create more fermentable sugars which will not only boost the body, but also the overall sweetness of the beer. (Jump to Solutions)

**Vegetal** : These flavors and aromas are in the same category as DMS, and are produced most commonly by sulfur compounds similar to DMS. These vegetal compounds are formed when the more complex sulfur compounds formed by the malting process are reduced during heating. This is why DMS and Vegetal flavor and aromas are formed when the wort is hot. It should be noted that vegetal flavors that come across as rotten vegetables, are more commonly caused by bacterial and wild yeast infections. Wet hops and/or excessive dry hopping can also lead to vegetal flavors and aromas. (Jump to Solutions)

**Vinegar-like:** Vinegar qualities tend to fall under the sour and acidic group, but on some score sheets you may tend to get a judge or two who will specifically say it is vinegar-like. While this still means it's acidic, but they are thinking the infection is coming from a specific source, the acetobacter bacteria. Acetobacter is what can turn wort into malt vinegar. (Jump to Solutions)

**Vinous** : Unless you are adding grapes, grape juice, or wine to the finished beer, the Vinous attribute is almost always a form of oxidation from aging of high gravity beers. (Jump to Solutions)

**Worty:** Worty beer is sweet, just like in the above section, but it is a more descriptive way to say that not only is the beer sweet, but specifically it is under attenuated. So whoever tasted the beer doesn't think that the sweetness is at all from any other factor other than that the fermentation ended too early. **** (Jump to Solutions)

**Yeasty:** While yeast flavors and aromas are a huge part of specific beer styles, if the flavor or aroma is of raw yeast or something unpleasant and meaty the cause is quite simply poor yeast health. At times, if yeast in suspension as well. This would happen most often in bottle conditioned beers with a lot of sediment. **** (Jump to Solutions)

Most Common Brewing Process Failures (not covered in off-flavors)

**Beer too Clear:** At first it doesn't really sound like a problem does it? Your beer is too clear? How can that be? Well, some beer styles should be cloudy, like a heffeweizen for example. So what could be the cause of your normally cloudy heffeweizen to pour crystal clear? Assuming that you used the proper yeast, the answer is simply that your yeast and any proteins that were in the beer fell out of suspension. This can happen as the beer ages and/or the longer you have it in cold conditions. **** (Jump to Solutions) ****

**Beer too Harshly Bitter:** At first glance the obvious cause would be too much bittering hops. But there are other causes of a harshly bitter beer. Your water chemistry can have a lot of influence over the perception of bitterness. Higher concentrations of bicarbonate or adding a lot of gypsum to your water can increase the perception of bitterness, as well as high concentrations of magnesium and calcium chloride. Water pH (which incidentally is also tied in with the water's alkalinity which is directly related to the hardness we just covered) can also influence the beer's bitterness. The pH of the beer can extract tannins in the beer, which many times come across more dry and grainy, but can also come across as harshly bitter. Too much dark roasted malt can lead to bitter flavors. Mold from improperly stored grain or wort exposed to mold spore can make the beer bitter as well. Some wild yeast and bacterial infections can make the beer unpleasantly bitter, but this is fairly rare. (Jump to Solutions)

**Beer Too Hazy:** While haze may not be a big concern as far as flavor and aroma are concerned, it can be the difference between taking a 1st place in competition or placing 2nd or 3rd. Sometimes haze is caused from the hops, dry hopping in particular will add some haze to the beer. Also grains like wheat and oats can add some proteins to your beer which will cause it to be a bit hazy. These are generally acceptable in the styles of which they are used. Unwanted haze is caused by proteins in suspension and can be caused by a few factors. A poor boil will not cause a good hot break to yank some of these proteins out of suspension, and adversely, a slow cooling phase will not allow for a good cold break. Both of these issues will leave more proteins in suspension than you may wish for leading to excessive haze. (Jump to Solutions)

**Beer too Hoppy:** By too hoppy, I do not strictly mean bitterness or IBU's alone. Hops also bring flavor and aroma to table. If a beer has too much hop aroma or flavor than what you are looking for, there is 1 main cause. The first is too many hop additions, late additions in particular. (Jump to Solutions)

**Beer too Malty:** If your beer is too malty, in that is too malt forward in the flavor and/or aroma (we are not just talking sweetness alone here), there are several factors to consider. The first is that the beer may have finished a bit too early, leaving a lot of unfermentable malt sugars in the beer. Another common cause is that if you are an all grain brewer, you may have mashed at too high of a temperature. An excessive amount of steeping grains or specialty grains can also lead to more malt flavor or aroma than you are seeking. One of the most overlooked components of this problem can again be your water. Higher sulfate levels or very soft water can reduce the perception of bitterness, therefore actually increasing the perception of malt. Water with higher sodium or chloride levels can also boost this perception. (Jump to Solutions)

**Body Too Full:** Not to sound overly redundant, but one cause of a beer that is too full in the body is too high of a mash temperature creating more unfermetable sugars than you were expecting. The over-use of highly dextrinous malts (cara-pils for example), caramel malt, or lactose will also boost the body. (Jump to Solutions)

**Body Too Thin:** On the flip end of the scale, you will have a beer that is too thin and watery. The cause of that will be highly fermentable wort caused by a low mash temperature. Too much water in your recipe also will not only lower the gravity, but also dilute the beer. More commonly in extract beers; you may add top up water, adding too much will dilute the beer essentially giving you less fermentables per volume, giving you a watery beer. Some enzymes and/or bacteria can break down more complex sugars with allows for more fermentation. In the case of enzymes (Clarex for example), this would normally not occur in the wild, but if you added some and ended up with a beer you felt was too thin, this would be the cause. In the case of a bacterial or other infection, the light body is also normally accompanied by unwanted phenols or esters. (Jump to Solutions)

**Dark Wort/Beer:** If you are an extract brewer using liquid malt extract, it is common for oxygen to react with the malt syrup darkening it. This is normal and often too be expected. Concentrated and extended boils will also darken the beer, as well as if your heat is too intense and you scorch the beer during boiling. (Jump to Solutions)

**Fermentation Ends Early:** If your fermentation ends too early, there are two main factors to consider. Fermentation or yeast health and fermentation temperature control. The cause of a beer whose fermentation ends too early is most commonly attributed to yeast health. The yeast were not healthy enough to complete the job and so they drop out of suspension. Temperature can play a big factor as well. While too high of a temperature may not be a concern for ending early (Unless you are fermenting above 100°F), too low of a temperature can cause your yeast to go into hibernation. (Jump to Solutions)

**Fermentation Too Active:** It may be difficult to tell during fermentation if your fermentation is _too_ active for the beer. But in hindsight, if you have some issues and remember the beer fermenting like mad or blasting out through the fermentor, it may have been you had an abnormally active fermentation. This is a hard one to come to a conclusion to because yeast can act differently from batch to batch and some fermentations are simply more active than others. If you do not normally have a healthy pitching rate or enough aeration, then suddenly you change that, you may find your fermentation seems overly active. You honestly will not know until you taste the beer. If the fermentation was too active you may end up with a lot of esters or fusel (solvent) alcohols. The cause would normally be too high of a temperature, but could also be a highly fermentable wort from a low mash temperature. Of course there is always the possible contamination in which case you would have your yeast fermenting right alongside a wild yeast strain, causing a very active fermentation. Again, this is not one to be concerned with until after you have had a chance to taste the beer. If your beer is fermenting harder than normal, don't get concerned right away. (Jump to Solutions)

**Final Gravity Too High:** When you are expecting a certain final gravity for your beer, based on numbers from brewing software ( _Beersmith, Beer Tools Pro, ProMash, Brew Target, etc_ ) you may not always get the exact number you were shooting for. But if your final gravity numbers are a lot higher than expected, and the beer is actually a bit sweet or worty, there are a few causes. The first and most common cause is that you did not pitch enough yeast. There simply was not enough good viable yeast for a solid healthy fermentation. Another cause could simply be that your yeast dropped out too early. This could be because of overall yeast health (including aeration) or that you had some temperature variations during fermentation that caused the yeast to go dormant. The third cause could be that the fermentation is done. The reason for this would be that maybe your mash temperature was higher than expected and you created more complex sugars that your yeast cannot break down. This leaves a lot more sugar behind and will give you a higher final gravity. Sometimes extract beers naturally finish a bit higher than expected because of the mash process that the specific maltster used. Finally, the yeast could have stopped because it reached its limit. You will find this commonly in higher gravity beers where the yeast hits its alcohol tolerance limit and just cannot thrive anymore so it drops out. **** (Jump to Solutions)

**Flat Beer in Keg/Bottle:** For Bottle beer there are few factors. The first, and most common is that you did not give the beer enough time in the bottle. While generally beer should be fully carbonated in about 2 weeks, depending on the yeast type, it may take a little longer. Another cause would be that the yeast is not healthy and just cannot produce any longer. Third would be that the condition that you are storing the bottles is too cold and the yeast just is not awake. Finally, the problem can be that you did not add enough priming sugar to your bottles. In kegged beer, you will have all the same conditions if you are using sugar to prime your keg as well as the following force carbonation issues. The Pressure is not high enough, you have too little headspace in the keg, the beer temperature is too warm to get the right amount of gas into solution, or you did not let it sit long enough under pressure. (Jump to Solutions)

**Head Retention Issues:** Actually, poor head retention can be caused by a large number of issues, some a lot more common than others. A common cause of head retention issues is the amount of alcohol in the beer. Higher alcohol leads to the beer not having the surface tension needed to retain a good head on the beer. Another common cause is there is not enough protein in the beer; this will be more common with beers that use adjuncts. Hard water can also contribute to poor head retention. Those are probably your most common causes. But other causes can be enzymatic breakdown of carbohydrates in the mash (extended mashing), high fermentation temperatures, and fatty acids released from oversparging. (Jump to Solutions)

**Light Wort/Beer:** If your beer is too light in color, there are really only 2 causes. You didn't use enough specialty or dark malts in your beer or even if feel you did because your recipe called for a specific amount of darker malts, it's possible that you had more water, or more overall volume than the original recipe called for, therefore diluting the beer. **** (Jump to Solutions)

**Over Carbonated Bottles/Keg:** For bottled beer the most common causes are that you used too much priming sugar or the beer was not done fermenting when you bottled it. In some cases, wild yeast and/or bacterial infections can ferment the more complex sugar chains and not only dry out the beer, but also over carbonate it as well. For kegging, the causes can be the same, except now you can add the amount of pressure you are force carbonating your beer with and the amount of time you keep it under high pressure. The temperature of the beer as you carbonate it can make a difference too. The colder the beer, the more CO2you can dissolve into solution. (Jump to Solutions)

**Slow Starting or No Fermentation:** In most cases this is strictly going to be a yeast issue. Most commonly it would be caused by under pitching. The next most common cause would be that your yeast was dead when you got it because of poor shipping conditions. Also, if you pitched your yeast into wort that was too hot, you could have killed off the viable yeast. Alternatively, if your wort is too cold you could have caused your yeast to go into hibernation. Last, it could also be that fermentation is taking place but you do not have a good seal on your carboy or bucket and gas is escaping elsewhere. If you see foam or bubbles (you may have to open your bucket) but no activity in your airlock, it's more than likely a seal issue. (Jump to Solutions)

Determining Likely Cause

So now that we have a bulk of the most common causes of flaws covered, how is it that you determine the most likely cause? At first it seems simple, and in most cases determining the likely cause will be obvious. But it may not always be a straightforward or even single answer. If you were making a beer, and you know that your house 80°, it may be evident that whatever issue you are having could be related to fermentation temperature. But what if you feel you did everything right and still ended up with some problems? How do you determine what the exact cause of your issue was? Let's look at how you can determine a cause of a potential bacterial infection which is causing a funky aroma and sour flavor in your beer from most likely to least likely cause. This will help us determine our theory, and take corrective action.

First you want to always considering the most common cause first. As much as you may never want to admit to yourself that there was a breakdown in your cleaning or sanitation process, it generally is the leading cause of most foul off-flavors. This doesn't necessarily mean that you did a poor job of sanitizing, it just means that perhaps you have a scratch in a piece of plastic equipment, maybe your hoses need to be replaced, or maybe you were a victim of wrong place at the wrong time. It happens. I guess my main point is to never think you're above the most simple of errors.

There are wild yeast and bacteria in the air at all times and it's also possible that a few colonies of some type of microbe may land in your beer during transfer or during the cooling phase. Your risk of this is considerably higher if you live near any fruit orchards. There is usually a lot of wild yeast on fruits and during days with moderate winds, it can carry the yeast some distance.

Next is to consider the environment you were brewing in. Try to think back as clearly as possible to anything that could have happened, even if you didn't necessarily see it. A good example I have is if you have children, young ones in particular (or even pets). If left unsupervised, a child or pet can be very curious. So if you brew outside and run into your house, there is a possibility (even if it is unlikely) that the dog could have licked some of the equipment or the child could have put something in their mouth or touched it with unclean hands. It happens.

Now that we have established three likely variables, we can look at our equipment, consider our variables, and recall our practices for that brew session. Just for the sake of closure, we will determine our factor. On that brew day the wife was gone and took the child with her. So there was no way the child came out and was playing with the cleaned equipment out of curiosity. There is no dog, so that's not even a consideration. Although on the brew day, you recall a there was a stiff breeze, you do not live near any orchards or farms. So it's highly unlikely you are at a slightly higher risk of wild yeast. Plus, as a general rule you cover your unfermented wort with tin foil to minimize the possibility of anything airborne dropping into your wort or that you could accidently drop something into the cooled beer. However, upon inspection of your equipment you notice that even though your carboys are fine, that your hoses are fairly old and slightly discolored. It's more than likely this is your main focus for the cause of the infection, and you simply throw out the hoses and head off to the hardware store to pick up more tubing.

Step 3: Create a Plan of Action

We have now come to the stage where you want to start thinking about what you want to do to correct the problem. You have learned what the common flavors and aromas of beer are, the causes of these flavors and aromas, and now we will look at common ways to correct these faults. Then using what you have learned, you can choose the best path to correct the flaw.

Solutions to Common Off-Flavors

**Acetaldehyde:** Giving the beer more time in the fermentor will correct this issue. If you have already kegged/bottled the beer, this flaw will diminish with age, so give it some time.

**Alcohol:** The most common correction you can make for a beer that is too high in alcohol is to adjust the recipe. There is a possibility you got a much better efficiency than the original recipe called for. Always check the notes on the recipe to see what the implied efficiency is. If the recipe was formulated assuming 62% efficiency and you ended up in the 80's that can make a difference. If your efficiency is higher than the stated recipe, just scale back the base grains. Aside from efficiency, the mash temperature can make a difference as well. If your recipe called for a mash temperature of 154 degrees, but you were only at 148, you are going to end up with highly fermentable wort. This means more sugars are consumed by the yeast and more alcohol produced. You can usually couple this cause with the beer being too dry or lacking mouthfeel as well.  
Finally would be fermentation temperature control. Pay attention to the highest threshold for the yeast strain you are using (that data can usually be online or in many cases the yeast packages themselves). I recommend staying a few degrees below that high side for sure, don't ferment right at the upper limit unless you are looking for particular flavors.

******Astringency (Tannic):** All of the solutions for an overly astringent beer involve mash health. The pH of the mash is paramount, so if you are not into water chemistry or understand how various grains impact the mash; use a buffer like 5.2 Stabilizer from Five Star. This is a great way to _help_ ensure your mash will be within an acceptable range. Just be aware that it can only buffer so much and is fairly dependent on the grain bill and your water profile, so if you continue to have issues after using 5.2, start getting more up to speed on the water chemistry aspect of your mash. Second, you will want to avoid over crushing and/or over sparging your grain. If you own your own mill, make sure the gap is only cracking the husk and not completely pulverizing the grain. When you are sparging, take readings every so often and stop sparging if your gravity gets to 1.011 or roughly 2.8 Brix.

**Barnyard:** In all cases, this aroma is associated with poor sanitation. With good sanitation practices. Even if you brewed a sour beer in previous equipment, you should not see any carry-over from those old batches. Some people who brew sours keep separate equipment for sour beers. I don't brew a whole lot of sours, but I do on occasion. The only thing I keep separate however, are the hoses. Everything else is cleaned well with brewery wash and then sanitized after use. I then rinse prior to the next use to remove any dust and sanitize again. If you do not brew sour beers, sanitation is still your issue. You will need to inspect all of your equipment for scratches or cracks, clean everything well, then sanitize it. Use heat if possible (Oven or Dishwasher). If you are trying to clear an infection and will rinse after, you can use a solution of bleach and water. I have used ¼ cup in 5 gallons of water, then let it sit for 15 minutes, then rinse thoroughly. Because you have to rinse bleach, I don't suggest using it as a sanitizer, but to clean equipment you can use it as long as you rinse very well. Plastic parts are cheap and easily replaced. In the case of a suspected infection, if you can afford to do so, I suggest replacing all plastic components.

**Chlorophenolic (** see also Medicinal **):** To correct a chlorophenolic issue, the number one solution is to use carbon filtration to filter your water. This is also probably the best solution. However you can use campden tablets to get rid of chloromines. You use 1 campden tablet to treat your brewing water (Specifically, 1 tablet is good for up to 20 gallons. So you can cut up a tablet into quarters and use ¼ tablet per 5 gallons). The reaction between the potassium metabisulfite and chloramine breaks the chloramine down and allows it to dissipate from the water as chlorine. If your water only has chlorine in it, you can let it sit out overnight uncovered and the chlorine will dissipate out of the water. Last, if you are using bleach for either sanitation or cleaning, you need to rinse rinse rinse. Use a no-rinse sanitizer like one-step, Iodophor, or Star San for sanitation. Why risk such a nasty off-flavor to save a dollar or two in your $25+ batch of beer you worked so hard on? Sanitation is arguably the most important aspect of making good beer. That is the one area you do not want to cheap out on.

**Catty:** If you don't like the catty aroma of certain hops, then research hop varieties you do enjoy and make a different choice. Drink hoppy beers early and don't let them age too long, or they may start to develop that catty aroma.

**Cheesy:** Use the freshest hops possible. Vacuum seal any unused hops, and store them in the freezer to help prolong the life the hops. If you have the ability, purging your storage container of oxygen with either nitrogen or carbon dioxide will help prevent oxidation of the hops as well.

**Cider-like** : Use the freshest extract possible from reputable sources. Limit the amount of corn sugar you use in proportion to grain/malt extract. Control fermentation to a few degrees below the top threshold of that yeast strain. Lastly, if none of the above applies to you, there is the possibility it is related to infection, so use standard sanitation practices.

**Diacetyl:** Just because your beer is done fermenting, does not always mean it is done. To ensure you do not get a lot of Diacetyl, let the beer sit for a few days after fermentation completes. If the yeast dropped out too early, it may not have cleaned up after fermentation. So if you have consistent diacetyl issues, you should consider measures to ensure better fermentation health. Proper temperature, good aeration prior to fermentation, and pitching enough yeast (Making a yeast starter) are the keys to a good fermentation. In lagers, diacetyl is absorbed more slowly due to the low fermentation temperature, so raising the temperature of the beer to 60 degrees for a few days will help clear that up.

**DMS (Dimethyl Sulfide):** A solid rolling boil for 60 minutes (90 minutes for high DMS Malts like Pilsner Malt) will reduce the DMS in your beer. Also since it will continue to develop in hot wort, cooling your beer as rapidly as possible is very helpful. The faster you can get that beer below 120° F the better. Also, since DMS is driven off in the boil, covering your beer while boiling or even while it's still hot during the cooling phase is not advisable.

**Estery:** The key to controlling esters is fermentation health. The less stressed your yeast is, the fewer unwanted esters they will produce. Decent aeration, a solid pitching rate, and fermenting your beer within the temperature range suggested for that yeast strain will keep the esters under control. While some homebrewing yeast producers claim you do not need a yeast starter, many homebrewers have come to the conclusion that you do. I used to stand up for the statements by yeast producers that the cell counts in the vial/pack are sufficient to ferment your average 1.050 beer without a starter. However once I started making a starter, my beers improved a lot. So I also fall into the camp of homebrewers who believe you need to make a starter. I think the reason is because of the factors of home fermentation. We can do a good job of controlling our temperature, but unlike a lab we don't always know if we have too much or too little oxygen in our wort. We also don't know the exact cell count of the pitch. We can calculate the pitching rate, but we don't have the ability to gauge our physical pitching rate like a lab does. I am also willing to bet there is considerable loss of viable during the shipping of yeast from point A to point B, and in some cases from point A to point B to point C. So while it may be true that perhaps the cell counts are enough in the vials or packs themselves at the time they leave the lab, by the time they to your home there may be a lot less viable yeast.

**Grassy:** If the grassiness of the beer is suspected to be hop derived. Just let it age a little longer. Also, you may not be a fan of dry hopping and that's OK. Consider other methods of late addition hopping like Hop Bursting (Adding large amounts of hops during the last 15 minutes of the boil). Consider other varieties of hops.

Poorly and improperly stored grains can also cause this, so use the freshest grain possible and if you store your own grain, make sure it's sealed tightly in a cool and dry place.

**Grainy/Husky** : The unwanted husky quality can be avoided by using proper mashing and sparging technique. Ensure that your grains are not over crushed, you should have them crushed just enough to expose the starches inside the kernel. Maintain the proper mash pH in the 5.2-5.6 range (5.3 is ideal), use water chemistry spreadsheets and/or a buffer like 5.2 stabilizer from Five Star. Do not over-sparge and stop if your gravity readings dip below 1.011.

**Medicinal (see also**Chlorophenolic **):** Filter your water through a carbon filtration system or used a trusted bottled water source that does not contain chlorine or chloramines. Avoid using bleach to sanitize your equipment. If you must use bleach on your brewing equipment, rinse VERY well. Medicinal flavors can also be signs of poor mashing processes, so pay close attention to proper mashing technique and your pH. Infections can also be a leading cause so if you suspect infection, clean and sanitize your equipment very well. If possible; replace all your plastic components.

**Metallic:** When cleaning your metal equipment, use a cleaner that will not harm the type of metal you are using. A good soak in a brewery wash, like PBW should get most residue out without scrubbing. If you need to scrub your metal components, use Barkeepers Friend because is made for stainless equipment. If you bottle, be sure that the rubber seal on the bottom of your caps is in good condition. If you do not suspect the flavor is coming from your metal equipment or caps, get your water checked out and check for high concentrations of Iron. You may have to use bottled water or purchase a filter that will help reduce the iron in your water.

**Musty/Moldy:** Store your grains in a cool and dry place. Never let them get damp or wet. Inspect all equipment for any signs of mold that may have formed or been forming on poorly cleaned surfaces. There is always the chance that some mold spores landed in your finished beer, in which case there is not a whole lot you can do fix that, other than keep your beer covered as much as possible during transfer phases.

**Over Carbonated/Carbonic:** For bottled beer stick to about an ounce of corn sugar per gallon of beer. Most bottle conditioned beers will use 4.5 to 5 ounces for a five gallon batch. If you exceed this amount you are going to be over carbonated and at risk for exploding bottles. For kegging, there is some dispute, but I tend to listen to the Homebrew Supply shops and according to most of them, you use the same amount of sugar in the keg as you would for 5 gallons of bottled beer. However many homebrewers use anywhere from ½ to ¾ the amount of sugar compared to bottling, so you may want to determine which amount works best for your situation. You can also use the method I use for force carbonating which is very fast and can get your beer fairly carbonated in just a few minutes. I keg my beer and put it in the fridge to get it down to a cool 38 degrees, usually overnight in the fridge will do the trick. Then attach the CO2 connector and bump up the pressure to 35psi. Lay the keg down making sure the CO2 connection post is towards the top. Sit in a chair and rock the keg back and forth with your feet for 10 minutes. That's it. If you need a bit more carbonation, let it sit at 12psi for a few days in the fridge. If you are force carbonating, you can refer the chart below for pressures and temperatures. The way this chart works is by that only a certain amount of gas can dissolve into the liquid at certain temperatures. Let you beer sit at these pressures and that volume of CO2 will be dissolved into solution. Generally this process takes about 2 weeks, but in some cases a little longer.

Force Carbonation Chart (Source: www.northernbrewer.com)

**Oxidized:** To minimize oxidation, be very gentle with the finished beer when transferring the beer to the secondary or to the keg. If you have a kegging system, it's a good practice to fill the keg and/or bucket up with CO2 gas when moving the beer. It reduces the likelihood of oxidation during transfer. Excessive age can lead to oxidation as well, so expect this in well-aged beers. If you are bottling beer, Oxygen absorbing caps can help reduce oxidation in bottles, as well as placing the cap on your beer and waiting a few minutes before capping. This allows some time for some dissolved CO2 in your beer to escape and create a protective layer in the bottle.

**Phenolic:** Fermentation control (temperature in particular) and sanitation are your keys to controlling phenols. Generally your most offensive phenols are attributed to chemical contamination (Chlorine or Chloramines in the water, residual cleaning agents, etc.). So if you are experiencing harsh medicinal or plastic-like phenols, the first place to look is your water supply if it is municipal, invest in an active carbon filtration unit. You can also build one fairly inexpensively. I will focus the next portion on unwanted phenols, because if you chose a strain of yeast that is known to produce phenols, you more than likely have done so for a reason. If you do not like the yeast derived phenols in beer, you should simply choose a strain of yeast that produces a cleaner tasting beer. But if you are experiencing an unwanted smokiness, clove-like character, or other spicy notes...I hate to break it to you, but you have some sort of wild yeast or bacterial infection in your beer. This can occur by no fault of your own, because bacteria and yeast are floating in the air all around us. So to reduce your risk, cover your beer as well as you can during transfer, or build a closed transfer system (shown here). The second source is poor cleaning or sanitization processes. Ensure all of you equipment is very clean and sanitized well prior to coming in contact with any cooled wort. Replace all plastic equipment and hoses if possible.

**Skunky:** There is only one simple way to avoid skunking your beer. That's to avoid exposure to sunlight. At the fermentation stage, make sure you keep your beer in a dark area, away from direct sunlight. If that is impossible, then cover your carboy with a cardboard box or wrap it in a towel. If you bottle it, as a homebrewer, you have control over the storage and aging of your beer. So using clear or green bottles is not as much of a negative factor as it is in commercial beer. Just be sure you keep the beer out of direct sunlight while storing it. Amber bottles offer the best protection, but as long as you keep your bottles in the case, green or clear bottles are fine.

**Soapy:** To avoid excessive fatty acids in beer, you need to ensure you have no bacterial infection. Because some fatty acids are formed during fermentation, these types of fatty acids are normal, and rarely exceed the moderate level. However bacterial or wild yeast infections can move these fatty acids levels to the above normal range. . Some newer hop varieties can also give a soapy flavor impression. ****

**Solvent:** Always ferment your beer in the recommended temperature range of the yeast you are using. ( _While specific yeast strains vary, you want to be in the 68°-72° F for ales and 45°-55° for lagers on average_ ). Excessive temperatures can lead to these solvent flavors and aromas. Also, if you aerate your wort with an aquarium pump or by shaking, you cannot over aerate. However if you use a pure O2 system, it is easy to overdo it. So if you are using the pure O2 system, dial back your time that you are pumping oxygen into the wort.

**Sulfur/Farty** : Sulfur is easily driven off. If your beer contains too much sulfur and you have not bottled or kegged it yet, just give it some time for the sulfur to leave solution. If you have the beer kegged, you can purge the sulfur from your beer easily by placing your gas line into the beer output post on the keg and open the pressure release valve. That way the CO2 will be forced up through the beer by way of the dip tube, and bubble out scrubbing the sulfur out of the beer. If you bottle, you can just wait and see if the sulfur dissipates with time. If not, swirling the beer in the glass will release the sulfur as well.

**Sour (acidic):** If you are experiencing unwanted sourness in the beer, you will need to review your sanitation and cleaning practices. Start by cleaning and sanitizing all your equipment, even if you are not currently brewing. Using heat if possible to sanitize your equipment. I know that this is not an option for a lot of our plastic equipment. In this case you should inspect everything for any scratches and discard anything that could come in contact with your cooled beer that has any scratches or cracks in it. I replace my hoses often, about every 2-3 batches. Make sure if you are using a no-rinse sanitizer you are making sure the equipment has been in contact with the sanitizer for the suggested amount of time, at minimum. If you really want to get fancy, you can minimize any possibility of wild bacteria or yeast falling into your beer during transfer by building a closed transfer system. (Shown Here)

**Sweet** : If your beer is too sweet, and you are an all-grain brewer. You may want to review your mash temperature. You may even want to double check that your thermometer is working properly. This has happened to me, where I was using a digital thermometer and it was off by about 10 degrees. I didn't even notice until one time I was going to boil some water and left the probe in the water. The water came to a boil and the thermometer was reading about 200° F. This was not good. That means that in at least several beers, when I was bringing it strike temperature, I was considerably higher. Since then, I have started using 2 thermometers to always keep the other in check. For a short time my beers were finishing higher than expected and I couldn't figure out why. I didn't consider mash temperature because as far as I knew, my temperatures were on.   
Another cause is your yeast stopping fermentation too early. Let's start with the most easy to correct, temperature. I keep repeating to keep your yeast strains temperature range in mind. Up until now it's always been about watching the high end. Now, you have to pay attention to the low end. If your wort gets too cold, the yeast will go dormant and stop fermenting. This will cause the beer to finish way too sweet. The next correction would be your pitching rate. Unless you are using dry packaged yeast, you will want to make a yeast starter if your beer is over 1.050 starting gravity. This will bring your cell count up to ensure you have a good solid pitching rate and have a healthy fermentation. You will also want to be sure there is enough oxygen dissolved in solution to help with yeast growth and regeneration. Even if you are doing a yeast starter, you want to aerate just a bit to ensure there is oxygen present as the yeast multiply to the levels they need to ferment your beer. Some people say you do not need to aerate if you used a starter with a stir plate because the yeast had oxygen during the starter phase. But even with a healthy starter, the yeast will still need to multiply. In order to do this properly, the yeast need oxygen. You may also want to add some yeast nutrient, but generally this is not required because your grain should have added all the nutrients your yeast need.

**Vegetal** : The same process to reduce DMS will reduce vegetal flavors and aromas. A solid rolling boil for at least an hour (90 minutes for Pilsner malt) will drive off the vegetal aroma and flavors. Do not cover your wort during the boil, so you can allow these unwanted compounds to be released during the boil. Cooling the wort to at least to below 120° F as quickly as possible will reduce the formation of vegetal and DMS aromas post boil.   
Another common cause is excessive late addition or dry hops. Because hops are essentially vegetation with chlorophyll. You will get some level of vegetative properties from the overuse of late or dry hopping.

If the cause is a bacterial or wild yeast contamination, you must clean and sanitize all your equipment. I highly suggest at a minimum replacing all your plastic hoses.

**Vinegar-like:** To clear this up, you will need to review your sanitation and cleaning practices. Start by cleaning and sanitizing all your equipment, even if you are not currently brewing. Using heat is a good way to sanitize your equipment if you can. I know that this is not an option for a lot of our plastic equipment, but it's viable for all metal, glass, or heat resistant plastics used in brewing. For your plastics, you should inspect everything for any scratches and discard anything that could come in contact with your cooled beer that has any scratches or cracks in it. I replace my hoses often, about every 2-3 batches. Make sure if you are using a no-rinse sanitizer you are making sure the equipment has been in contact with the sanitizer for the suggested amount of time, at minimum. If you really want to get fancy, you can minimize any possibility of wild bacteria or yeast falling into your beer during transfer by building a closed transfer system. (Shown Here)

**Vinous** : To minimize oxidation, be very gentle with the finished beer when transferring the beer to the secondary or to the keg. If you have a kegging system, it's a good practice to fill the keg and/or bucket up with CO2 gas when moving the beer. It reduces the likelihood of oxidation during transfer. Excessive age, which is the most common cause of the vinous character in beer, can lead to oxidation as well and so you can expect this in well-aged beers. In some bigger beers, this character is not always considered a flaw. If you are bottling beer, Oxygen absorbing caps can help reduce oxidation in bottles, as well as placing the cap on your beer and waiting a few minutes before capping. This allows some time for some dissolved CO2 in your beer to escape and create a protective layer in the bottle.

**Worty:** While you can try to use the solution for fixing a beer that is too sweet, but focus on the fermentation health aspect of the solution more so than the mash.

**Yeasty:** If you are bottling, you will want to try to minimize the amount of yeast pulled over into the bottling bucket. Don't worry; there is plenty of yeast in suspension that you can't really see which will work just fine for carbonating your bottles. If you are not careful when siphoning over your beer to the bottling bucket, or if you bottle directly from the primary, you can end up with too much yeast in the bottles. You can also end up with too much yeast if you use too much priming sugar at bottling or kegging (if you are not force carbonating in the keg). While most of the time you will end up with an over carbonated beer, and possibly a bottle bomb, if your bottle does not explode you can end up with excessive yeast in the bottle. For kegging, the same rules apply. You will tend to get some yeast sediment, which will usually come out in the first pint or two you draw off the top. However if you have constant issues with excessive sediment in your kegs. You can cut the bottom off your dip tube by an inch, which will draw your beer from an inch higher in the keg. The amount of beer you lose in the end is minimal, about 1 to 1 ½ pints at most.

Solutions to Common Brewing Process Faults

**Beer too Clear:** If you are looking for a cloudy beer, but end up with one that is crystal clear, don't worry too much about it. If you bottle, and your beer style is one like a Heffeweizen you can swirl the yeast up from the bottom of the keg or bottle prior to serving. You could also change the recipe of your beer to contain a bit of wheat malt, which has some proteins that can contribute to a cloudy beer (think Witbier). However, overall you shouldn't be too concerned with a beer that is overly clear. Unless you are looking for more flavors from the yeast, the proteins that cause haze or cloudiness in beer don't really contribute to flavor or aroma. ****

**Beer too Harshly Bitter:** Usually you can rule out hops in a beer that is harshly bitter, because the key word I am using is harsh. But do not rule out the hops, as they can be a contributing factor. In order to determine if the harsh bitterness is coming from the hops, you will want to do a search for your particular hop varieties used in your beer and look up the cohumulone level. Most brewers pay close attention to Alpha Acids, which gives us our bitterness, but ignore the cohumulone levels. Cohumulones, in high levels can lead to a harsh bitterness from the hops.

Commonly, your water profile will lead to the harsh bitterness I am speaking of though. Higher concentrations of bicarbonate or adding a lot of gypsum to your water can increase the perception of bitterness, as well as high concentrations of magnesium and calcium chloride. Water pH (which incidentally is also tied in with the water's alkalinity which is directly related to the hardness we just covered) can also influence the beer's bitterness. So pay close attention to your water chemistry. So while you may or may not fully understand how to adjust your water, our goal is to find a solution. If a water report shows you to have high concentrations of bicarbonate, you can try to filter your water, or simply use a bottled source. You can get gallon bottles for under a dollar, so using bottled water is fairly inexpensive.

The pH of the beer can extract tannins in the beer, which many times can come across as harshly bitter, so using a buffer like Five Star's 5.2 stabilizer can help if you suspect pH issues. If you are comfortable with water chemistry in your brewing process, pay close attention to the pH of the sparge in particular so it does not go outside that 5.2-5.6 range and extract tannins from the grains.

Reduce the amount of roasted grains if you are using roasted grains in your beer as well, excessive use roasted grains can change the pH, so pay attention to your use of these grains.

**Beer Too Hazy:** Fixing haze issues can be fairly straight forward. We have many options at our disposal to control the clarity of our beer. The most simple is to use additives to the boil. Irish moss or Whirlfloc Tablets will help grab a hold of proteins in the wort, and pull them out of solution and allow them to fall to the bottom of the kettle as you cool your wort.

If you are an All Grain brewer, taking time to allow your grain bed to settle will help a lot. If you are a fly sparge brewer, this will not be much of an issue, but if you batch sparge, catch some of your runoff in a ½ to full gallon jug after each sparge and pour it back into the top of the mash tun. This will allow the grainbed to "set" between rounds of sparging. If you are a brew in a bag brewer, this is one of the risks you run by not sparging. You lose the benefits of filtering your wort through the grainbed. But don't worry; there are a few other solutions you can try as well.

You can use post fermentation clarifiers. Clear unflavored gelatin is a popular choice among brewers and is very easy to use. You only need to heat about ½ to 2/3 of cup of **cold** distilled or filtered water to a clean and sanitized Pyrex cup. Add 1 packet of clear unflavored gelatin (or a teaspoon of gelatin you buy at the homebrew shop). Allow the gelatin to bloom (rest) for 15-20 minutes. Heat the water to 150° F -160°F (Do not heat above 170° F or you will end up with Jell-O) to get the gelatin to fully dissolve. Then pour the liquid into the beer and allow it to sit for 24-48 hours. The gelatin will bond with particles in the beer like yeast and proteins and help them to sink to the bottom. There are other options out there you can explore as well such as Sparkolloid powder, Isinglass, and Polyclar for example.

Then of course you can always invest in a filter. While you will have clear beer, you should be aware that this will also strip out your yeast and some of your small particulates that you may actually want in the beer. While generally you may not notice too much as far as flavor and aroma go, some people claim that using a filter that is too fine, really takes away from the flavor and the vibrancy of their beer.

Beer too Hoppy:  A beer that is too hoppy is easy to fix. Again, I'm not talking strictly bitterness I am talking the overall hop character which includes flavor and aroma. Bitterness can be controlled in three different ways. The first is to adjust your hop choice to a lower alpha acid choice for bitterness. Different varieties bring levels of bitterness and different types of bitterness ranging from a bracing or sharp bitterness to a soft round bitterness. The second way is reduce the time and/quantity of hops. It goes without saying that fewer hops would bring lower levels of bitterness, but also the shorter amount of time in the boil will reduce the level of bitterness. Third is though water chemistry. High levels of bicarbonate in the water will increase the perception of bitterness, as will a highly skewed ratio of bicarbonate to sulfate. So obtaining a water report will give you insight into if water could be your issue with bitterness.

If your beer contains too much hop flavor or too much hop bitterness, you have two options. The first is to let the beer age. Hop character will diminish with time. This is why IPA's and other hoppy styles are best enjoyed fairly fresh. Your second option would be to reduce the amount of late addition hops in your recipe. Either though reducing the quantity, or changing the hop type.

One final consideration is your balance between the malt and the hops. It could be that your hopping levels are OK, but perhaps you have too much residual malt sweetness that is washing out some of your bitterness, aroma, or flavor. In which case, you may want to check out the next section.

Beer too Malty: When the beer is too malty you can of course balance this out with a bit more hop bitterness. However, if your recipe was properly formulated, and you end up with more malt character than you wanted, there are a few simple fixes you can try. The first is to simply double check your recipe. Are you using too much specialty malt? Excessive use of caramel malts or other specialty malts can lead to more malt flavors and more malt sweetness than you are expecting.

The next option to check is your mash temperature. You will want to verify that your thermometer is actually working as it should. It's possible that if it is not reading accurately, you are mashing at a higher temperature than you think. Reducing your mash temperature will yield more fermentable sugars and fewer residual unfermentable sugars. This will help dry out the beer, and in some cases reduce the malt flavors.

Another fix would be to ensure you are using good fermentation practices to ensure your yeast is not pooping out too early leaving behind a lot of malt sugars. Proper pitching rates, aeration, and fermentation are paramount in ensuring your beer is fully attenuated and your malt flavors and residual malt sugars are where you expect them to be.

Last, you will want to check your water. Obtain a water report (if possible) from the water source you used and check the sulfate levels and/or the ratio of sulfate to bicarbonate. High sulfate levels can enhance the perception of maltiness in the beer.

Body Too Full: If you used highly dextrinous malts in your recipe, like cara-pils, you will want to reduce the quantity in the next batch. The use of caramel malt, or lactose will also boost the body so be aware of the amounts used.

There are some enzymes you can add to your beer that will break down the complex, normally unfermentable sugars in your beer and help reduce the body. Some people report that a few drops of Beano in the wort will help break down some of these sugars through enzyme action. There is also an enzyme called Clarex you can purchase that will break down these long chain sugars as well.

Finally, mash temperature plays a large role in body. Any mash you do over 154° F will result in a fuller bodied beer. So reduce your mash temperature. If you are sure that your mash temperature was reading right on, I would check your thermometer to ensure it is reading accurately.

**Body Too Thin:** Watch the amount of water you use to top your batch if you are an extract brewer. It may be better to have less yield and a better beer than to make sure you get 5 gallons exactly. Take a gravity reading and if you are way over what you expected, go ahead and top up. But if you are fairly close to the range you were expecting, you are probably better off to cut your loss of volume and opt for the better tasting beer. Same holds true for All-Grain brewers. Don't sparge with so much water that you end up with a few gallons more just because there are still sugars in the mash tun. Once you get to your pre-boil volume, go ahead and just start your boil.

If you used an enzyme like Clarex, be aware that it can have a negative impact on the body of the beer. If not, review your sanitation process, because wild yeast and bacteria can consume long chain sugars that brewer's yeast cannot. Therefore lowering the body of the beer.

In some cases it may be a recipe flaw, and although you love how the beer turned out, the body may be lacking. In this case, the addition of more dextrinous malts, like cara-pils or dextrin malt can help boost the body the beer. Also, along the same lines of recipe formulation, pay attention to your mash temperature. Anything below 154° F will start to produce the more highly fermentable wort, and leave behind fewer unfermentable sugars. This will give you the medium to light body beers. Remember, you always want some unfermentable sugars to add to the body and overall balance of the beer. A beer that is watery thin, and bone dry is not a very enjoyable beer to say the least.

Dark Wort/Beer: The solution here is pretty straight forward. If you are an extract brewer, the extract will darken both as the extract ages, and as you boil it. To minimize this, you should use the freshest extract possible. Adding extract late in the boil (last 15-20 minutes) will also help reduce the darkening of the wort. (see late extract brewing method in Appendix I)

Extended boils and the over-use of dark malts will plague both the extract and all-grain brewer. So be aware of this to help reduce the problem of your beer being much darker than expected.

Fermentation Ends Early: You have 2 main options to look at if your beer is done fermenting too early or you have what's called a stuck fermentation. The first is overall yeast health. You want to be sure that you pitched enough yeast for the wort you produced. If you produced a higher gravity wort, you will want more yeast cells than if you were pitching into a 1.040 beer. There are online pitching rate calculators you can use, but in most cases making a yeast starter is all you should require. Unless you are doing a huge barleywine, a starter will get you right where you want to be. Making a starter will also ensure that the yeast you are using is viable and healthy. If you are using dry yeast, you should rehydrate it according to your yeast manufacturer's directions. In most cases it's as simple as adding the packet of yeast to ½ cup of clean filtered or distilled 75° F water (60° F for dry lager yeast) and give it 30 minutes. You can also use ½ cup of cooled wort if you wish. If you are using filtered or distilled water, it may be a good idea to boil then cool it just to ensure there is no chance for infection.

Proper aeration is also a factor to be considered for overall yeast health. I should also note in this section that yeast will have a range of alcohol tolerance. If you exceed that, your yeast will not be able to withstand the environment and drop out, ending fermentation as well.

The final consideration is fermentation temperature. If your beer is fermenting too cold the yeast will go dormant and drop out of suspension. You can easily remedy this by bringing your wort to a warmer temperature and gently rouse the yeast by swirling it back up into suspension.

Fermentation Too Active: This one is impossible to diagnose during fermentation because every batch will act differently. Even if it is the same recipe, you can have a very active fermentation one time, then the next it will appear to be not so active. If you do determine that you have negative effects on your beer, and recall thinking the fermentation was over active, there are a few ways to fix it the next time around. The first is fermentation temperature. A warmer temperature, above 72 degrees will give you a very active fermentation. Unfortunately, the excessively warm fermentation temperature will also give you unwanted flavors aroma, ranging from estery (fruity) to solvent-like higher alcohol flavors. Keeping your fermentation temperature within the acceptable range for your particular yeast strain will help ensure this is not an issue.

If you accidently mashed at a much lower temperature than you anticipated this, can be fixed by tweaking your process if need be to account for changes in environment or even equipment failure. For example if your thermometer is reading off by a few degrees, you will end up with a different mash all together. It may not seem like much of a difference on paper, but the difference between a 148° F mash and a 153° F mash will make a big difference in wort fermentability. So be accurate in your mash temps.

Final Gravity Too High: The most common fixes for a beer whose gravity finishes too high is very similar to the beer that finishes too sweet. You may want to review your mash temperature. You may even want to double check that your thermometer is working properly. Too high of a mash temperature will yield more unfermentable sugars that will leave you with a final gravity that is higher than you wanted.

Another cause is your yeast stopping fermentation too early. Let's start with the most easy to correct, temperature. I keep repeating to keep your yeast strains temperature range in mind. Up until now it's always been about watching the high end. Now, you have to pay attention to the low end. If your wort gets too cold, the yeast will go dormant and stop fermenting. This will cause the beer to finish way too sweet. The next correction would be your pitching rate. Unless you are using dry packaged yeast, you will want to make a yeast starter if your beer is over 1.050 starting gravity. This will bring your cell count up to ensure you have a good solid pitching rate and have a healthy fermentation. You will also want to be sure there is enough oxygen dissolved in solution to help with yeast growth and regeneration. Even if you are doing a yeast starter, you want to aerate just a bit to ensure there is oxygen present as the yeast multiplies to the levels they need to ferment your beer. Some people say you do not need to aerate if you used a starter with a stir plate because the yeast had oxygen during the starter phase. But even with a healthy starter, the yeast will still need to multiply. In order to do this properly, the yeast need oxygen. You may also want to add some yeast nutrient, but generally this is not required because your grain should have added all the nutrients your yeast need.

For extract brewers, this may come with the territory.  Since you have no control over the mash process, you are the mercy of the malting company as far as the fermentability of the wort. Generally, they shoot for a middle of the road approach and shoot for a beer that will almost always yield a medium body. The way to combat this is to add a bit of corn sugar to your process, you may have to experiment with how much to add for your particular malt extract of choice. But the addition of corn sugar will add more 100% fermentable sugars which will in turn produce a bit more alcohol which will thin out the beer as well as help dry out the beer. Just be careful not to add too much. You could end up with a boozy or hot alcohol character.

Flat Beer in Keg/Bottle: For bottled beer, I wouldn't attempt any other options unless you have waited at least 3 weeks. Sometimes, carbonation can even take longer in cool conditions. But 3 weeks is the minimum I would wait before I started to be become concerned. If your bottled beer is flat after 3 weeks, I would move it to a warmer location and swirl each bottle after it has reached that warmer temperature, then give it a bit more time. If after a month, the beer is still flat, you may have some real difficult to fix issues. You could try purchasing some carbonation drops from your homebrew supply shop and add one to each bottle, but you are running the risk of over priming your bottles and end up with exploding bottles.

For kegged beer you have hope. If your beer is failing to carbonate, and you used priming sugar, you can try the same steps above for bottling, or you can just force carbonate. Using the carbonation chart I showed earlier, you can force carbonate your beer. If you are in a hurry, you can increase the pressure in your keg to 30psi, lay the keg on its side with the gas in post on the top, and gently rock the keg back and forth for 10 minutes. This will give you some decent carbonation in a very short period of time.

**Head Retention Issues** : If you have a high alcohol beer, poor head retention comes with the territory. You could try to combat this with the addition of higher protein malts in the recipe, like some additional wheat or carafoam malts.

There are commercial head enhancing agents on the market that you can buy, that aid in the head formation and retention. If you like that route, you are more than welcome to explore that route.

Since the head formation is directly related to the body of the beer, any enhancements you can make from the above sections on the addition of body could help with the head formation and retention. This would include the addition of the malts I listed above.

The quality of the CO2 and carbonation you use will have an impact on the head retention and formation. For example, if you use the quick shake method above, your beer will carbonate, but the quality of the carbonation will not be the same. You could end up with poor head formation. This is why some people claim that bottle conditioned or keg conditioned beers seems to form a better head. They tend to have smaller more tightly compacted bubbles. If you have the ability to use a nitrogen and CO2 mix, or beer gas, that would be your best option. But that tends to be more expensive as well.

The last option is an interesting one, the use of high alpha acid hops can aide in heat retention. This may come in as handy knowledge for high alcohol and highly hoppy beers, like Double IPA's and American Barleywines. High alpha acid hops are also high in isohumulones, which will aide in head retention.

Light Wort/Beer: If your beer is too light, it may be diluted. There is no fix for that in post-production. But you may boil longer if you are still in the boil phase.

The second cause, there is no post production fix......in a way. There is a product called Sinimar from Wyerman malting. It is a relatively flavorless and sugarless extract made from the Carafa family of malts. This product can be used to darken wort, but does require some boiling to sanitize it. You could add some Sinimar to a cup of water, and boil it, then add to the beer for some color. This may not be the best approach, but if you are looking for a quick fix, this may the ticket. Be careful though, a little goes a long way in a 5 gallon batch. If you are not careful, you could end up with a black beer.

Last, would be a recipe change for the future. You will want to add more caramel or other darker malts to your batch in the next run. But as long as the beer tastes fine, and how you wanted it. I wouldn't worry too much about color. Because color is not a flavor and flavor is what is most important.

Over Carbonated Bottles/Keg: For bottled beer, there is not much you can do once the bottles are carbonated. You could agitate the beer to get some CO2 out of solution in the glass, but other than that, you're stuck with what you have and will have to make adjustments using less priming sugar the next time around. If you are sure that you used the proper amount of priming sugar, you may have bottled your beer prematurely before it was done fully fermenting. You then ended up with too much sugar in the bottles. So ensure that you give your fermentation ample time to finish, and always check your gravity readings to make sure they are no longer declining. Even if you no longer see airlock activity, that does not guarantee the beer done.

Bacterial or wild yeast is always a consideration in these cases, but it also tends to be accompanied by other off flavors. If you suspect infection, take the proper sanitation and cleaning steps I have laid out several times over in this section, or skip right to the general infection section.

For kegged beer, you have options. First you want to reduce the pressure to your keg, or turn it off completely. Then pull your pressure release valve and release all the CO2 pressure in the keg. Repeatedly shake and release pressure until you get to the level of CO2 you are happy with, and then just keep the beer under serving pressure to ensure your carbonation levels do not increase.

Slow Starting or No Fermentation: This is going to be a yeast health issue through and through. If you are looking at less than 48 hours, I would continue to wait. If your sanitation practices are up to speed, you shouldn't have any issue prior to 48 hours. If it's been more than 48 hours, you may have to take action. The easiest and fastest course of action is to re-pitch some yeast. If you keep a packet of dry yeast on hand, that is a good insurance policy to ensure you will at least be able to make beer. If you have a local homebrew supply shop, you have the option of running to the store to pick up the same variety of yeast you pitched. That is really the only option you have for existing wort.

To prevent this from happening, you will want to aerate your wort after cooling. Proper aeration will give the yeast the proper conditions to multiply and grow fairly quickly. I use a pure O2 system, but shaking the beer for 15 minutes, or the use of an aquarium pump with an inline filter and stainless steel aeration stone will work just as well.

You will also want to pitch enough yeast. To ensure you are getting enough yeast, you can pitch 2 vials/packages of yeast, or use a yeast starter. Making a yeast starter is your cheaper option, although is a bit more work than just pitching 2 vials/packages. But pitching enough healthy yeast into your wort will also ensure a healthy fermentation that kicks off fairly quickly, less than 24 hours in almost all cases.

Correcting General Infection Issues

In each section above where infection could be an issue, I listed some common fixes for correcting infections. I thought it should have its own section to cover general infection correction processes because it's so important.

When it comes to infection, nobody wants to mess around with trial and error and deal with infection after infection, you want it done and over in one blow. It may seem like a lot of work, but following some of the processes below will help eliminate the problem, and sometimes it does cost a little bit of money to do so. If you know where your source of infection is, that can be a huge help as well. For example, if you open a bottle of beer and it tastes bad, is over carbonated, and gushes out of the bottle, but no other bottle acts like this. You can be fairly confident that the infection was due to a single bottle. This does happen. In my case, what I do is just toss the bottle. Bottles are cheap and easily replaceable, especially if you drink craft beer as well as your homebrew. However if single bottles are valuable to you, you can focus on just wiping out the infection in that one bottle. Now, if you take the same problem and it's many (or all) bottles then you know the infection took place anywhere from the racking cane all the way back to your chilling phase. In this case you can follow the processes below. Please note that these fixes apply to any equipment that comes in contact with the cooled beer. Anything from before and during the boil is much more forgiving.

  1. Replace all plastic components you are able to, especially if there are any visible scratches. Replace all hoses that come in contact with the cooled beer.

  2. Clean any plastic components that you cannot easily clean. I use a q-tip in my hoses and blow from one side to the other. There are also some brushes that are made to clean dip tubes. These can be used, but they could scratch softer plastics. Then soak everything in a Star-San Solution of 1.25 teaspoons per gallon. This is slightly higher than the recommended no-rinse dosage, but it will not harm your equipment. Allow a minimum of 3 minutes contact time. Then rinse and store the equipment.

  3. For non-plastic equipment (stainless, copper, glass), your best bet is to clean the equipment and treat it with heat. For Kegs, be sure to remove all gaskets and O-rings because the heat will melt them. You can sterilize bottles and other equipment with heat, but it can take hours. Contact with a solid boil for a minimum of 15 minutes will kill any yeast or bacteria that could be harming your beer. Baking the equipment in 250 degree oven can yield the same results as boiling (remember this part is sanitizing, not sterilizing). Just be careful with glass because the rapid heating and/or cooling can shatter the glass.

  4. If you don't like the thought of using heat, you can treat your equipment with chemicals. Bleach in a concentration of 2 tablespoons per gallon will kill just about any wild yeast or bacteria on your equipment. Allow for 20 minutes of contact time. This is twice the recommended dosage for no-rinse use so you **will** need to rinse very well after this treatment. Again, this is a treatment to kill whatever is infecting you and is not intended to be a pre-brewing sanitation recommendation. Personally, I do not advocate the use of bleach as a sanitizer for brewing because if you do not rinse well it can cause some pretty nasty off flavors. But bleach does work well for eradication.

You can also use Star San or Iodopher. I like to use above the recommended dosages for any possible infection issues, just to kill the wild yeast or bacteria. For Star San I use 1 ¼ teaspoons of Star San in a 1 gallon jug of distilled water, you can use the same dosage for Iodopher. Rinse after 3 minutes of contact. I have not had many infection issues over the past few years, but if I were to run into one today, I would use Star San over the bleach solution I posted above. However, I have used the bleach solution with success.

  5. After any of these treatments rinse and dry your equipment. You should be infection free in your next batch if you treated your equipment and replaced any inexpensive plastic or rubber components.

Preventing Infection

Ultimately the goal is to avoid infection in the first place. I have a few tips for minimizing unwanted infections. Some may seem like overkill, but they have worked for me.

  * Clean your equipment as soon as you can after brewing. I know it's not the fun part, but cleaning your equipment before it has time to dry will really make clean up easier. I know some guys who wait to clean until the next day this can cause issues with mold/bacteria growth and leave behind residuals you may not see.

  * Sanitize after cleaning. It may not be necessary, but it certainly doesn't hurt. After brewing I clean my equipment then I like to give it a quick spray of sanitizer.

  * 15 minutes before bottling or kegging, I like to spray the air in the area with Lysol. My theory is that this will knock down and/or kill some of the airborne yeast and bacteria in the area. I know it doesn't sanitize the air, but I feel it helps reduce any airborne microbes.

  * Cover the beer! After I insert the racking cane/auto siphon I cover the top of the fermentation vessel with tin foil. I also keg, and cover the opening of the keg with tin foil. This helps eliminate any unwanted wild yeast from falling into your beer.

  * You can build a closed transfer system. I have not been ambitious enough to do this myself, but below is a drawing of the concept. Some brewers use this method of pushing the beer with CO2 from the fermentation vessel (normally a carboy) into the keg. This is a scaled down version of how many breweries transfer their beer from tank to tank.

Correcting General Fermentation Issues

Aside from cleaning and sanitation, fermentation health is the #2 area to focus on to prevent a wide variety of beer faults. A healthy fermentation takes a little bit more work than dumping in the yeast and forgetting about it, but the rewards far outweigh the minimal effort it takes. There are many steps a brewer can take, but below are 4 basic steps to start with.

  1. **Pitch the proper amount of yeast.** Generally you should make a starter for any beer over a gravity of 1.045 that is using a liquid culture (See Appendix 2 on how to build a stir plate at home). You can use online pitching rate calculators to figure out how big of a starter you need for a specific beer, but generally speaking you are usually OK with a 1 or 2 liter starter using ¾ cups of DME per liter for most beers, big beers and lagers may require a lot more yeast. With a starter you are doing 3 things. You are ensuring your yeast that you purchased is viable and did not die during shipping, you are giving your yeast a good chance to wake up out of their dormant stage, and you are giving them a chance to build up their numbers so they are not as stressed during the lag phase.

  2. **Aerate the wort.** Even if you use a starter with a stir plate, you should aerate your wort. Some people say you do not need to aerate your wort if you use a yeast starter with a stir plate because the yeast gets oxygen during that starter phase. While that last part is true, yeast still need oxygen to multiply in a healthy manner. Because you are pitching more yeast by using a starter, you are not pitching all the yeast required for fermentation. Therefore your yeast still needs to multiply and still requires oxygen. You can aerate your beer by shaking it for 10 minutes without a stopper in, or you can use an aquarium pump with an inline HEPA filter for about 20 minutes. While it's not required, the use of a stainless steel airstone will really help. The airstone will produce tiny bubbles that will be more easily dissolved in the wort. With these 2 methods you cannot over aerate your wort because there is only about 21% oxygen in the air. So it would be very difficult to get too much oxygen in the wort. A third option is to use pure oxygen to aerate your wort. This is my personal preferred method but you have to be careful. When using pure oxygen it is possible to get too much oxygen into the wort and you will end up with fusel alcohol flavors and aromas. With a pure oxygen system you use a small portable oxygen tank, like the ones you get at a hardware store, a small regulator, and a stainless steel airstone. You can fully aerate your wort somewhere between 30 seconds and 1 minute. This is an advantage because it not only cuts the amount of time that your beer is exposed to the air, but the air you are pumping in is clean and free from any wild yeast or bacteria.

  3. **Ferment at the proper temperatures**. The optimal temperature that your yeast will perform best at varies from strain to strain. But generally speaking for ales you want to be in the mid 60's to the mid to low 70's and for lagers you are looking at 45°F-55°F. Your best bet is to check the website of your chosen yeast producer and verify the temperature of the strain you are working with. I understand that not everyone has a cooler or refrigerator they can use to control the temperature of fermentation, in which case you may be better off brewing beers by season. For example brewing beers that can withstand slightly cooler temperatures in the winter and brewing ales that have a higher temperature tolerance in the mid-summer. If you choose to invest in a refrigerator or chest freezer to ferment in, you will be very happy with the results and so will your yeast. Keep an eye out, sometimes people sell used chest freezers and refrigerators for cheap (even free sometimes) and it's a solid investment in your beer if you have the room.

Some people also use bins with water in them to help keep temperatures down. You can freeze water in old milk jugs and place those inside the water as well. Some people even lager like this. Personally I tried this and was not happy with the results. I think the temperature fluctuates too much for the yeast to not become stressed. If you have the ability to change the ice jugs a few times a day, this may work. But for me, I a small chest freezer was a much better option.

  4. **Rehydrate dry yeast.** I promise you that you will have plenty of people telling you that this step is unnecessary because in the past all they have done is sprinkle the yeast on top and let it go and it fermented just fine. This is in part, true. You can sprinkle the yeast on top and it will ferment, but it's not ideal. The rehydration process is simple, free, and takes very little time. Yet the benefit to the health of the yeast is well worth it. As a comparison, I can drive my car with a tire pressure over or under the recommended PSI. The car will move and I may not even notice the difference while driving. But it will show in my gas mileage and it will help with the life of my tires. To rehydrate your yeast, all you need to do is add the packet of yeast to ½ cup of clean filtered or distilled 75° F water(60° F for dry lager yeast) and give it 30 minutes. You can also use ½ cup of cooled wort if you wish. If you are using filtered or distilled water, it may be a good idea to boil then cool it just to ensure there is no chance for infection.

Step 4: Test the Theory

From here on out, things get a lot easier and a lot more straight forward. The process from here is quick and matter of fact. So now you have familiarized yourself with the various flavors and aromas of beer, both good and bad. You have looked at likely causes of these faults, and have a general idea of the solution options you have. It's time to test the theory. This is the part where you actually put your plan and assessment into action. Everything up until now has been a theory, even if you think you know what went wrong it's still technically a theory until you can test the correction and verify the results. That is what you do now. You use all the information that you have to come up with the best plan of action. I will outline an example below, try and pinpoint the possible causes based on the information I provide in the scenario.

It's the middle of summer and you figure you will brew an ale, you decide to brew a cream ale because although you cannot get down to lager temperatures you do have a fairly cool basement that averages around 70 degrees in the start of summer. You also want a beer that will be fairly quick and you want to be able to enjoy it by the middle of summer. The ingredients were an all-grain cream ale kit from your local homebrew supply shop, which you know has a fairly fast turn over on ingredients. Overall your brew day goes as planned and you hit all of your numbers. Your mash temperature was right on the mark, your starting gravity is right where your recipe indicated it should be, 1.050, and when you filled the fermenter it came right up to the mark of 5 gallons. You use an immersion chiller to cool the wort, and because of the groundwater temperature being slightly warmer, it takes about 40 minutes to cool your wort. You aerate the beer with an aquarium pump with an in-line HEPA filter for 20 minutes to try to get more oxygen into your wort. You are going to use a dry version of an American Ale yeast, so you rehydrate the yeast in some warm clean water. You pitch the yeast and fermentation starts fairly quickly, in about 12 hours and continues to ferment at a very good pace. You have a nice solid fermentation going. To your surprise in 2 days the beer is done fermenting so you take a gravity reading and decide you are going to give it a day or two to rest before you bottle it. After 2 days, you take another gravity reading and you confirm the beer is in fact finished fermenting so you bottle it using the corn sugar that came with the kit. You let it sit for 2 weeks, before having some friends over to taste it.

OK, I'll give you a minute to digest all that before we taste this beer. So you crack it open and you make note of the following. The beer has a slight corn-like aroma and has a fair balance between malt and hops, although is slightly leaning to hop side. There is some fruitiness to the beer. The flavor has some decent bitterness to it, but is slightly sweeter than you expected. You also note that there is a smooth creaminess in the mouthfeel that feels almost oily. You don't care much for that character and wonder if your friends get the same thing. One friend states he thinks the beer is good, and doesn't think it's too sweet, but there is a buttery character to the beer, it reminds him slightly of buttered popcorn. Your second friend thinks this is a very good beer and thinks it tastes slightly like honey, but also detects the mild sweet corn flavor. One thing he notes is that he feels you can have a bit more hops. He does not detect anything that is butter-like or oily in the beer but does say there is a slight apple character. So from here, what would be your assessment based on the data given? Your conclusion may differ from mine, and that's OK. Let me explain what my findings would be based on this scenario.

_It appears that for the most part the beer was a success. Especially for how quickly it finished. There were no detectable higher alcohols; it was not overly dry or overly sweet. The fermentation seems to have been healthy and while some people noted the beer was slightly sweet, that style should be slightly sweet up front. The corn-like flavor and aroma was not out of bounds for this style. DMS in low levels is acceptable in this style, so the corn-like aroma is not a concern...unless you don't like it. The thing to note was the buttery aspect, and as you detected the oily slickness. This is generally an indicator of diacetyl, which is not acceptable in this style. If you don't mind this flavor/aroma then there is no need to make adjustments unless you enter beer into competitions. If you are not a fan of diacetyl it's time to look at your process and see where you may have gone wrong. By looking at the scenario, and knowing about what the causes are of diacetyl, it appears that the formation of diacetyl was unavoidable. It is a natural byproduct of fermentation. However, in our hast to get this beer bottled and served, we probably did not give the yeast enough time to clean up the diacetyl before we racked the beer off the yeast. This theory is supported by the note of your friend that there is an apple-like character to the beer. You also noted there is some fruitiness, so you should re-evaluate that character to see if it is more green or fresh apple than a generic fruit character. The apple character could be a sign of_ _acetaldehyde another sign of pulling the beer off the yeast too quickly. To correct this issue, we would come to a plan of action that states the next time we are in a hurry to get a beer in the bottles for serving, we either need to give it a few additional days or just accept that the beer will have some diacetyl._

Plan for Failure

Some answers will be straight forward and you will get the results you desire on the first pass. However, some problems are a bit more complex because they have more than one cause. It's a good idea to plan for failure. What I mean by this, is if you test theory 1 and end up with the same result, you need to be ready and willing to try the next most likely cause. Even if you believe that cannot be the issue. I know some people who cannot take any constructive criticism of their beer, even when they ask for it. I can't tell you how many times I have had someone ask me to try the beer and tell them what I think. Then when I do, if I detect anything slightly negative, it's a battery of excuses or denial that it cannot be. "I can't have DMS, I boiled for an hour", for example. Well that's great but how fast did your beer cool? What type of grain did you use? How vigorous was the boil, was it rolling boil or a gentle boil? Then of course you have the complete and utter denial of a beer that may be infected. Having good sanitation practices is not always enough. People need to remember that these yeast and bacteria are in the air, and your beer is vulnerable during transfer stages. Granted the alcohol, pH, and hops help offer some form of protection but it's not a 100% guarantee that some wild yeast cells are not drifting in the air at the time of bottling (when your beer is usually exposed for the longest period of time) and contaminates your beer. It's not common, but it does happen. Plan for failure and have a backup correction plan in case the first fix happens to not correct the issue.

Step 5: Verify the Results

Self-Evaluation

It goes without saying that in order to verify the results of your solution you have to evaluate the beer for yourself. If you refer back to the section on evaluating your beer, you will have to determine if you feel the flaw has been eliminated. If so, then you have succeeded. But don't let your guard down. It's easy to make beer. It's easy to make good beer. The hard part is consistently making good beer. That is the goal. Remember, there are always people out there telling you that you don't have to do this or you don't have to do that. For the most part, they are correct. You don't have to do anything above and beyond to make beer. Just toss some malt extract in some water, boil it, add hops to the boil, cool it, and add yeast. But it's the extra steps you take to ensure a good quality product each and every time that will set you apart from the casual brewer. I understand that people have monetary limitations, I have them too. So you don't have to make all of these changes overnight if you cannot afford it. I slowly bought or built new gadgets over the years and I am still doing minor upgrades and changes to this day. It keeps things fun and exciting as you have a something new to look forward to. But trust me, the advanced techniques that the award winning homebrewers and the pros use to make good beer really does make a difference so don't just toss all that advice you hear out the window. Even if you have won a few awards, there are improvements that can be made to up your game even more. Just never forget that.

Always Get a Second Opinion

Getting a second opinion is very important. You can be your own worst critic, and that is the reason you sometimes need an outsiders point of view. The power of suggestion can actually cloud your senses. What I mean is that sometimes, if you are searching for a particular flaw, chances are you can actually trick yourself in believing it is there. So if you do detect the flaw is still in your beer, get a second or third opinion. Bring a friend over and ask them to honestly tell you what they think about your beer. Don't be discouraged if they are don't like the beer or detect something you don't. Everyone's taste is different and some people are more sensitive to some flavors/aromas than others. But the one thing that outsider will not be doing is searching for a particular flavor unless you tell them to. So test the waters to see if they detect something a bit off about the beer or not. Be sure try to get a specific answer from them. "It tastes weird" is not a good description. Ask them, what is weird about it? Does it taste like plastic? Does it taste smoky? Is it metallic?

For other feedback, you can always send the beer into competition. There are many competitions throughout the country going on during any given month. Sending your beer to competition is a good way to get some honest unbiased feedback. The judges don't know you, they don't know the process you used to brew, and they have no stake in stroking your ego or hurting your feelings. There are a lot of good judges out there who will give your beer a fair and honest review, even though sometimes people don't agree with fair and honest feedback of their hard work. I highly recommend sending a beer into competition as a troubleshooting tool, and who knows...your beer may not be as bad you think (remember we tend to be our own worst critics) and you may walk away with a medal on a beer you don't think is that great. But no matter what, you almost always get some form of good feedback from the judges. Even though there are some judges out there who do a poor job, they tend to be in the minority.

Step 6: Document the Findings

This step is optional and I will cover it all in a few short sentences. If you want to document your findings, that is up to you. You can do so in a journal or right in your brewing software. Most brewing software includes a place for notes, and you can add any issues you have or have corrected right in the notes. Even if you use a spreadsheet instead of software, you can easily document anything you wish to cover. The way I use the notes section in my brewing software is to document any changes to the recipe I want to make in the next go around. For example if I want to use a different yeast strain the next time I brew that recipe, I will make a note of it in the notes to "change to XXXXXX yeast". Then the next time I brew it, if I preferred the change to the original, I will reflect the change in the recipe itself. So really, while documenting your findings are important in some applications, in the homebrew application taking notes may not be as big of an issue as in other ways this model is used.

Appendix I: Late Extract Brewing

First let's take a quick overview of what happens to extract in extract brewing. When you brew with extract, there is some level of unavoidable oxidation of the extract, this is more prominent in liquid extract than dry extract. There is no way to completely avoid this, it's just the nature of the beast. To minimize this, you want to find the freshest extract possible. For the most part (hopefully) the days of going to the homebrew supply shop and finding a can of extract with a bunch of dust on it are gone. Homebrewing is becoming so popular that most homebrew shops don't have a big issue with product turn over. But, be aware of this. Dust on the can or bag is a not a good sign of fresh extract. This oxidation darkens the extract and in some opinions is what leads to the cider or tin-like flavor that some people claim "all" extract beers have.

Aside from this oxidation darkening, you will have some level of kettle carmelization (technically it's a Maillard reaction, but everyone calls it carmelization). This reaction is a darkening and flavor changing reaction that is more noticeable in concentrated boils. Such as if you are boiling 3 gallons of wort in a 5 gallon pot. This will produce darker wort, and in the end a darker beer, as well as provide some minor changes to the flavor.

To combat this, most people use the late extract method, which is a very simple concept. You add ¼ of your extract at the start of the boil, that's it. Just 25% of your total extract addition. So if you are using 6 pounds of extract in a beer, you only add 1 ½ pounds at the start of the boil, then during the last 15 minutes of the boil you would add the remaining 4 ½ pounds. Not only will you get better color and a more consistent malt flavor, but also you will get much better hop utilization because you don't have as much concentrated sugars in the boil. It's very important to be aware of this, because if you don't make adjustments to your extract batch, or mark your extract as "late addition" in your brewing software, you can end up with a beer that is more bitter than you anticipated. But if you use (on average) 20% less bittering hops, or make the proper adjustments in your software you will be fine. You can also consider this, if you are an extract brewer who doesn't get the bitterness they feel they should be getting. Switching to late addition extract may solve your problem.

Appendix II: Building a stir plate

I will show you a quick project you can put together in less than an hour with minimal purchased parts, most of these you may already have on-hand laying around the house. Even if you purchased all the parts the total should not exceed $30 tops. The one I built cost under $10. I only had to buy the potentiometer, the switch (which I added later), and the quick connect terminals. It really helps if you have access to old computer parts. Here is what you will need.

1 cigar box or old jewelry box or equivalent -$8  
1 6 or 9 volt DC Charger (any old cell phone or other charger type will work)- Free  
1 Potentiometer and knob- $4  
1 Push button switch (optional)-$3  
1 Computer cooling Fan- $0-$7  
1 Rare Earth Magnet from a hard Drive $0-$7  
2 male and female Quick Connect terminals $2

The first step is to cut the DC connector (when it's not plugged in of course) and split the wires. Do the same for the fan. You need to find what wires connected to each other make the full circuit because many of the charger cables are both black. Most case fans are a bit easier because they may be black and red. To do this, connect the wires together until you get the fan to spin. Mark the pairing wires so you know how to create the loop pictured in the diagram you will see below. Think of the connection between the power supply, fan, and potentiometer as one loop (you can add an on/off switch as well if you wish). So once you find out what wires paired make the fan spin, you will connect wires below as shown below in my crude wiring diagram. Upper left is the plug, below is the potentiometer, and the big square is the fan. As you can see the red wire connects to the potentiometer, then the red wire on the fan connects to the other terminal (sometimes the potentiometer has 3 prongs, 1 of them is not used). The two black wires connect between the fan and the power supply to complete the circuit. Your wires may not be colored, which is why you test between the power supply and the fan to find the wire pairings.

Center the magnet the best you can on the fan and attach it by using super glue. Centering the fan is critical to prevent wobbling and to get the proper spin on the stir bar. (See below image)

Some people attach the fan to the lid. I chose to measure out wood standoffs on the bottom and glue them to the bottom with wood glue. Either way, the goal is to get the fan and magnet as close to the lid as possible without touching it.

Below you can see how simple the wiring is. I used quick connect crimping terminals to connect the wires. Easy as pie. On the right is just a key that I can lock the box if I choose, it's not part of the stir plate assembly.

I'm not sure how much you can see from this picture, but it's a close up of the potentiometer. Obviously you need to drill holes to get it into the box properly.

Below is just a rear view of the power cable going into the box.

Below is the end result. You will need a flask and stir bar once the stir plate is complete. I purchased a 1 1/2″ X 5/16″ stir bar. You use the potentiometer to control the speed of the fan. Since this photo was taken I have also added an on/off switch which is nice. If you don't want the switch, you just have to plug or unplug to the unit to turn it off or on.

Appendix III: Making homemade caramel for taste evaluation

These are beer caramels I make at home. The original recipe was based on some caramels I saw made on the Food Network Show, Good Eats. I have changed some of the ingredients to make them beer caramels, which have been very popular to serve around the holidays. Making these caramels will give you a much better understanding of the flavor and aroma of true caramel. You will find what many of us think of as caramel, is not the real thing, what we think of as caramel is actually more like toffee.

Ingredients

  * 1 ¾ cups sugar
  * ¼ cup plus 1/8 cup water
  * 1/8 cup of stout, porter, Belgian Dubbel, or your favorite dark beer. 
  * 1/2 cup light corn syrup
  * 1/4 teaspoon cream of tartar
  * 1 cup heavy cream, room temperature
  * 2 teaspoons soy sauce
  * 8 tablespoons unsalted butter, cut into 8 pieces, at room temperature
  * 1 teaspoon coarse sea salt

Directions

Line the bottom and sides of an 8-inch square pan with parchment paper.

Combine the sugar, water, beer, corn syrup, and cream of tartar in a heavy 4-quart saucepan and put over high heat. Stir occasionally until the sugar has dissolved. Cover and continue to cook for 5 minutes.

Meanwhile, combine the heavy cream and soy sauce in a liquid measuring cup. Have this and the butter standing by.

Remove the lid from the sugar mixture, and attach a candy thermometer to the side of the pan. When the sugar mixture reaches 230° F, reduce the heat to medium and cook, without stirring, until the syrup is a golden color and is approaching 300° F, about 6 to 7 minutes. At this point, there is less likelihood of any crystallization, so gently swirl the pan to break up any hot pockets.

When the temperature approaches 350° F, it will turn deep amber. Remove the pan from the heat, and gently swirl again to break up all of the hot pockets. Cool for 2 minutes.

Carefully incorporate the cream and soy mixture and the butter into the pan. Stir to combine. Return the caramel to medium heat, stir until the butter is completely melted, and continue cooking until it reaches 255° F. Remove from the heat and pour into the parchment-lined pan, tap gently to release air bubbles.

Cool on a cooling rack for 30 minutes, and then sprinkle evenly with the salt. Continue cooling on the rack for an additional 3 1/2 hours. Cut into 1-inch pieces and wrap individually in parchment. Store in an airtight container for up to a week.

Resources

Palmer, J. (2008). _How to brew, everything you need to know to brew beer right the first time_. Brewers Pubns.

Mosher, R. (2009). _Tasting beer, an insider's guide to the world's greatest drink_. Storey Publishing.

_2008 bjcp style guidelines_. (2008). Retrieved from <http://www.bjcp.org/docs/2008_Guidelines.pdf>

_Brewers association style guidelines_. (2013). Retrieved from <http://www.brewersassociation.org/pages/business-tools/publications/beer-style-guidelines>

More Beer. (Unknown). _Off flavors in beer_. Retrieved from <http://morebeer.com/themes/morewinepro/mmpdfs/mb/off_flavor.pdf>

Northern Brewer. (Unknown). _Kegging overview_. Retrieved from<http://www.northernbrewer.com/documentation/Kegging.pdf>
