- Alright, welcome to ProDev.
I see some familiar faces.
Is anyone new to Pro-Dev?
Awesome. Welcome.
ProDev stands for
Professional Development,
and it's a way for us
to to dive more deeply
into a coffee topic, to a
coffee-professional audience.
Now, anyone's welcome to come.
You don't have to
work in coffee.
You don't have to
have a background,
but it's definitely geared
toward people who do
and who want to learn more.
Otherwise, you can
feel a little lost
or overwhelmed with
the information,
but it's not to present you
with any definitive answers,
it's just to say, here's
some research we did
about this topic, and
here's what we found.
What do you think?
It kind of becomes, hopefully,
you will actually leave
with more questions
than you had when you came in.
That's kinda the goal.
So, welcome, and
thanks for coming.
Great, this is what
we're gonna do today.
We're gonna define fermentation:
what is it, really?
We're going to unmask
the fermentation stage
of coffee processing and talk
about how those
things are different.
Is coffee true fermentation?
We're going to discuss
the innovative approaches
to processing coffees.
A lot of people are trying
a lot of different things,
so we're gonna talk about
what some of those things are.
This definitely
won't be definitive,
and taste what's going on
out there in the world.
That the last part.
We're gonna taste different
processing techniques
in the fermentation tank,
all derived processing that's
experimentation derived
in the fermentation tank.
So, very excited.
We'll have plenty of time,
hopefully at the end, for
questions, conversation.
I always look
forward to that part.
Great.
So, what is fermentation?
Alan and Victor are gonna pass
out some fermented things.
What we're going to taste is
something that's not fermented
versus something that is.
So, we have tea, black tea,
and kombucha, fermented
with black tea.
- [Male] Tea and kombucha.
- They look very different.
Think about what you're tasting
and what the difference
is between the two.
We're also going to
taste two breads:
one that is fermented,
a sourdough,
and one that has
no fermentation,
just yeast to help it rise.
So, while I talk about
fermentation and what it is,
you guys can taste
the difference,
and then we will talk
about it in a minute.
So, dictionary-type
definition of fermentation:
an anaerobic cellular process
of breaking down a substance
by bacteria, yeasts, fungi,
or other microorganisms
into simple organic
substances and energy.
So, often, that's creating heat.
So, essentially, we
just have microbes
that are eating something
and generating energy.
Yeasts break down larger
compounds like sugars
into smaller ones like alcohol.
And that's why kombucha has a
little bit of alcohol in it,
whether they say it does or not,
because those sugars
have been devoured,
kind of like Pac-Man
style, into alcohols.
Since yeasts and other microbes
are present in the air,
spontaneous fermentation can
always happen at any time,
if the environment is suitable.
So, if I have my banana
smoothie sit on my counter
for a couple of days,
spontaneous fermentation
is going to start
happening because heat,
time, proper microbes
available, et cetera, right?
Fermentation can also be
completely intentional,
and we create these recipes
and use specific yeast strains
to generate a specific
result, right?
And the idea is that are
all these different yeasts
in competition to
thrive, and so what we do
is we select a yeast that
overpopulates the yeasts
we don't want,
that they win out the battle
for food, and they take over.
So, we can select yeasts.
And there are many factors
that affect fermentation:
temperature, like I
mentioned, warm things.
That's why we have
refrigerators, right?
Time.
If I don't leave something
out for long enough,
it's not going to
ferment, necessarily,
or fermentation won't
run away from me.
Amount of food,
so, how much sugar is involved,
how much sugar is in that.
My banana smoothie
has a lot of sugar,
so that will
ferment more quickly
than something else that's
not a banana smoothie.
The microorganism strain.
Certain strains act differently,
the amount of the
starting strain.
So, it's almost, of course
we think about it as
dose, time,
temperature, variety,
very brewing type of variables.
Any questions about
what is fermentation?
So, fermentation and food.
Let's talk about how
fermentation relates
to food, first.
So, as we've tasted those teas,
what are the differences
between the plain black tea
and the kombucha?
'Cause kombucha really
is just tea, sugar,
and a starter culture.
And we use temperature and
time to develop that, right?
So what are we noticing
in the flavor difference
between the kombucha
and the iced tea?
- It's fizzy.
- It's fizzy.
It has some liveliness to it.
Absolutely.
Can be some of that energy
that's being released.
Some of that alcohol is
also some of the energy.
It's sweeter, right?
Is it sweeter than
the black tea?
There's obviously sugar in it,
and all of those
sugars haven't yet
been consumed by the microbes.
It has that kind of funky,
vinegary flavor going on,
where the black tea obviously
doesn't have any of that.
So what about the two breads,
if you've tasted those?
(faint audience response)
More air, like we talked
about the fizziness
of the kombucha.
Sure, but there's
that sour flavor.
So, there's a fermented
flavor, right?
Does anybody here eat kimchi?
Anything like that,
those kinds of foods?
There's a funkiness, and
a definite sort of tang
to those foods, right?
That is present in these
that we just tasted, right?
- [Audience] Yeah.
- Yeah.
So, that is the fermentation
that we're tasting.
So fermentation, as
I sort of alluded to,
historically, has been used
for the preservation
of food, right?
Because we ...
We help the good
bacteria to grow
and overpopulate the
harmful bacteria,
so we have this food that's
preserved without refrigeration,
before there was refrigeration.
I know in Korea, they bury
their kimchi so it stays cool,
but it also has good bacterias.
Food producers, like
beermakers, winemakers,
cheesemakers, et cetera,
they create specific foods
using specific microbes
and recipes that balance
all those variables
we talked about:
the temperature, the time, the
certain strains of the yeast,
and that kind of thing.
Like, for sourdough bread,
bakers are using
a specific recipe
and manipulating those
variables to create a product
that they're looking for.
They want that sour flavor
in their sourdough bread.
Imagine that.
The most common species
of yeast that is used
in the fermentation
of food and alcohol,
and if I butcher
this, I apologize:
Saccharomyces cerevisiae,
which is brewer's yeast.
So, we're all pretty familiar
with that on some level,
whether we know it or not,
if we eat or drink
any of these things.
And when making
wine, beer, kimchi,
any kind of fermented
food, the yeast is allowed
to eat the available energy.
The available energy is
the form of carbohydrates,
like sugars.
So, that's why we put
sugar and tea together
to make our kombucha,
so that the microbes
can eat that sugar.
And what they're
releasing is alcohol
and acids, essentially.
So the pH is going down
and alcohol is created.
So certain wines, they let
the sugars be completely eaten
and go all the way dry,
so that it doesn't taste
as sweet as, for instance,
your kombucha tasted.
And it has a more drying finish
'cause almost all of the
sugars have been consumed
by yeast and microbes.
Does this make sense?
We following?
Great.
And the longer the
fermentation goes,
the more alcohol, the more
gas, and the lower the pH,
the more acid is created.
So that's why kombucha
is not super alcoholic,
because we don't let that
fermentation take off
and eat all of the sugars.
And I just alluded
to, deciding when
to stop the fermentation
is the decision
of the person who's
making the product,
based on flavor,
desired alcohol content,
those kinds of things.
Fermentation has a distinct
and identifiable
flavor component
in the final product, right?
We all can taste, probably,
when we're eating sauerkraut
versus when we're
eating coleslaw.
I mean, they're different,
but there is also
that funk, that sour,
that alcohol, that vinegar
kind of a flavor, right?
So keep that in mind
as we move forward
and talk about coffee.
So how is coffee
fermentation different?
Does coffee taste like kimchi?
- No.
- Yes.
- Oh.
I've never had coffee
that tasted like kimchi.
I'm sorry that you have.
(audience chortling)
- [Male] There was a problem.
- Yeah.
Does it taste like
sourdough or kombucha,
that funky, sour,
vinegar flavor?
Hopefully, by the time
it's made it to us,
maybe our coffee departments
have tasted coffee
that is like that, but
ideally, we haven't.
It hasn't gotten
all the way to us.
So, when we talk about
fermentation in coffee,
we're talking about a
step in the processing.
Farmers, producers,
green coffee buyers
refer to this stage of the
processing as fermentation,
And really, in wash coffee ...
We're gonna do a quick
overview of the wash process,
but it's right between
depulping and drying.
And really, the idea is it's
removing the sticky mucilage
from the coffee seed.
So, that's what you see
here in the photograph,
is mucilage on coffee seeds,
and we're using microbes
to remove that mucilage.
That's what that step
of the process is for.
Does this process contribute
to the flavor of coffee?
This is the big question
that we will tackle today,
but I can tell you, we won't
definitively solve today,
much to all of our chagrin.
I like clarity, check
the box, you know,
but we don't get that today.
A lot of big questions
with no real answer,
but we can get closer,
and hopefully by tasting, also,
we can have our own
personal experience
about how this contributes.
We wanted to mention this
just to put it out there:
to make things more
confusing, a lot of people
call overripe cherries fermenty,
like, oh, in a natural
processed coffee.
In a processed coffee where
there a lot of natural sugars,
because the fruit is
still attached to the seed
as is it's drying, people will,
an overripe coffee can ...
People can call those
natural processed coffees.
"Oh, this is a fermenty coffee."
It's actually overripe, and yes,
there's totally some
fermentation happening
in that cherry,
but what we're talking
about today is true,
the fermentation stage,
and we're kind of leaving
that natural processed
coffee behind.
The overripe tends to present
as sour fruits in the cup,
and can happen.
That's why extreme attention
to detail is really important
when you are processing
natural coffees
or honey-processed
coffees, any processing
where there is more
sugar available.
For example, last
year, our Kabawa,
which is from Uganda,
our Kabawa Natural was
put on plastic tarps,
and then they had a
really heavy rain,
and it was very warm,
and plastic is not breathable.
And so heat generated,
and did cause a little
bit of fermentation.
It still made it to our menu.
It was still good, but
it definitely tasted
a little bit more wild
than it did this year.
So, that one thing
that happened,
true fermentation
was likely happening,
but it's not always
going to go so far
as to be like, oh, put
on the compost pile.
It's no good.
It just changes, it can
change flavor slightly.
In the wash process,
that fermentation stage
we're going to talk about,
if that's left too long,
that's where we start to talk
about real fermenty flavors,
which are little
bit more savory.
And, we'll talk about that soon.
More like savory and oniony,
as opposed to that sour fruit
that you find in overripe.
Does that all make
sense, that difference?
Hope we didn't
over-complicate it
by even mentioning it, but ...
Okay, quick overview
of coffee processing.
Just to make sure we're
all on the same page,
we wanted to step
through it real quickly.
Coffee cherries generally
ripen from green to red.
Can be orange-yellow.
If left too long, the cherry
can become purple and shriveled.
You can see up in the top
of that branch, there,
the dark purple cherries.
Those would definitely
have overripe qualities.
Most cherries contain
two seeds inside.
Those seeds are what become
our coffee beans, right?
And the cherry is handpicked,
and then the coffee is floated.
Oh, I want to mention,
too, that when the cherry
is handpicked, if anybody
here has eaten many grapes,
and you pick the grape
off from the Stem,
or off of the vine,
you have a little hole
right where the
stem was, and some
of the fruit is exposed,
and that can happen
with coffee, too.
So, if we don't process
that coffee immediately,
fermentation can start happening
with the fruit that is exposed.
Aida, who we work
with really closely,
started experimenting.
These are her coffees.
Experimented with using
a knife to cut the stem
instead of handpicking
the cherries.
And she had great results.
Terribly inefficient with labor,
very expensive to
do, but she loves ...
She loved it.
So that just shows you that
there really is a difference
between actually picking
and cutting the stem.
So there is some
exposure of fruit.
There is a little
bit of fermentation,
but if we process quickly, then
that can get taken care of.
So after they're picked, the
cherries are then floated,
which means anything
that floats to the top
is either overripe or underripe.
So we can skim those
way, get rid of those,
and then only take the
coffees that are below.
So that first stage
happens with all coffees.
Now this is specific
to the wash process.
So after the float test.
coffee cherries are depulped.
On the left here,
you see a depulper,
And the coffee goes in the top
and these short teeth
sort of tear the cherry,
and the cherry goes in,
it's spit in the back.
You can see a pile of cherry,
and then the seeds are
spit into the front.
These are depulped seeds here,
and then this is the cherry.
The cherry can be,
is very commonly used
as compost on the farm,
but also, of course, can
be made into cascara tea.
And then we have fermentation.
The sticky depulped seeds
are then put in a large tank
for the fermentation
process to begin.
So, you see, there, a
depulper is attached
to the side of the tank.
They go right in there, and
they can then be fermented.
The tanks are usually
made of concrete, ceramic,
like ceramic tile,
stainless steel.
They can even be plastic.
It really varies.
You see a lot of photographs
of concrete tanks,
but it can vary.
We talk about two types
of fermentation processes:
underwater, which is like this.
The coffee seeds, the sticky
seeds are covered with water
for a certain amount of
time to let the microbes
do their magic on the mucilage,
or without water, kind of
like you see on the left side.
They're not covered in water.
They're just sitting there dry.
They're not actually dry.
They're just sitting there
dry, exposed to the air,
which has natural
yeasts and microbes.
This part of the process
can take anywhere
from six to 72 hours, which
is a huge range of hours.
It just really depends
on the producer.
I mean, so many things,
their style, whatever.
And after the mucilage has
successfully been removed,
they're then washed again
to get all of that off,
and then they move
on in the process.
When the coffee
seeds enter the tank,
they're kind of like
sticky, slippery.
You can tell that there's
something on them.
And then when they
leave the tank,
they feel like
polished river stones
that are more sort of
clean to the touch.
You can feel that they're clean.
And then, they go
on to be dried.
The coffee seeds are
still in parchment,
so they have this
protective layer over them,
and they are laid out to dry,
either on a patio
as you see here,
or in raised beds,
which is more ideal.
The coffee is turned
fairly regularly
so that it dries evenly.
We like to dry ...
Coffee is typically dried to
a 10 to 12% moisture content,
but I talked to
our coffee manager,
and he was like, "Actually,
ours is a little bit lower."
So, we do more like a
nine point something
to 10% moisture content.
And then once those are
dry, the beans are bagged up
and placed in a warehouse
until it's time export them.
And then, upon exporting
is when they're hulled.
So they go from
this sort of ....
cream color to,
we expose the green seed
underneath that parchment.
And then they're sorted
for size and density,
exported to where
they're supposed to go.
So, now, we're
gonna get specific
about the fermentation
tank and what's going on.
So, as I mentioned
before, the goal
of the fermentation step
is to fully break down
that mucilage and dissolve
that layer from the seed
so that we can then go
about drying the coffee
without anything sticky,
without extra microbes
attached to mucilage.
It helps the drying
process be sped up.
But what's really happening,
is fermentation really
the best word for that?
Because if we think
about what we tasted,
and what we talked about
as foods being fermented:
beer, wine, kombucha,
kimchi, sourdough bread,
those all have this distinct
flavor that we can recognize
as this is fermented.
But in coffee, we
don't have that.
So we were questioning
as a group,
when developing this ProDev,
is that actually fermentation?
So we went through
a couple of terms.
So, we talked about maceration.
So the definition of
maceration is to soften,
decompose, or separate
into parts by the action
of a solvent.
Does that sound accurate to
you all with what's going on?
Yeah.
It sounds pretty good, right?
We could say that the water
with the microbes is our solvent
and it's softening, decomposing
the mucilage to remove it.
But what about when
we have fermentation
that is without water?
Where's our solvent?
Right?
So, it's like,
okay, not perfect.
We weren't satisfied.
So, okay, well, fermentation.
Again, fermentation is the
anaerobic cellular process
of breaking down a substance
by bacteria, yeasts,
fungi, or other microorganisms
into simpler organic
substances and energy.
It's a lot of words,
but essentially,
that's definitely
what's happening, right?
Microbes are eating sugars,
which are removing this thing
and creating this
specific environment.
So that's definitely
what's happening,
but we don't love this
definition because,
or at least, our group
didn't love this definition
because we are a
little bit of a,
I don't know if you've noticed,
a fermentation crazed
culture right now.
Everyone's talking
about fermentation.
There's a cold case at
Whole Foods devoted just
to fermented things.
And this doesn't ...
I can't go around saying
coffee's fermented,
because it doesn't
have that flavor.
It doesn't have live
probiotics in it.
It just didn't feel like it
correlated exactly right.
I don't know if you all
agree with with that.
That definition just
feels a little off.
It's not zingy, so
it just didn't feel
like a perfect definition.
But there is this
other definition
that someone in the
coffee industry,
she's more in the
yeast industry,
but she talks about it as
microbial de-mucilage-ation.
Say that even two times, slowly.
Not easy.
That is more accurate,
because you're
just using microbes
to take off the mucilage.
Boom. Perfect.
So that resonated with everyone.
That resonates with her,
as really the most complete
and accurate definition.
It doesn't leave
any question marks.
It doesn't associate it with
something else that it's not.
But nobody calls it that.
Nobody is gonna call it that.
Lucia might keep
calling it that,
but at the end of the day,
coffee buyers, coffee producers,
are communicating
about fermentation.
That's what they call it,
so that's why we're gonna
keep calling it that.
But this is definitely the
definition that we landed on
that felt most true,
or the term, anyway.
Does that feel the most
true to you all as well?
Can you accept that
term, if you can say it?
Just don't say it out loud.
Just say in your head.
So, now that we're
clear about language
and we can kind of conceptualize
what's actually happening,
let's dive a little further
into how those microbes
are breaking down the mucilage.
So, when the coffee arrives
into the fermentation tank
it's already populated
with stuff, with microbes.
Soil has it.
Air has it.
The tree, the shrub has it.
All of the implements, the
depulper has microbes on it.
So, it's just picking up
a natural sort of flora
along the way.
And the tank itself, depending
on what the material is
and how often it's cleaned,
concrete is really
porous, stainless steel,
I don't know if anybody
has stainless steel,
but ceramic is less porous.
So that will make a difference
as to how many
microbes are available.
So depending on
what the microbe,
the natural, wild
population looks like
will depend on how
long this process takes
and what it kind of looks like.
The population of wild
microflora is really very dense
and is made up of yeasts,
bacteria, and filamentous fungi.
So that means is just fungus
that isn't a mushroom.
So it doesn't have a
fruit like a mushroom.
It's more of that spongy
mycelium-looking kind of thing.
So that is what will be on it,
and that population
of microflora
begin consuming the sugars.
And as that's consuming sugar,
lactic acid and acetic acid
is produced, which then
starts lowering the pH
of the fermentation
tank, totally.
Whether it's underwater
or without water,
this stuff is happening.
And aside from removing
the mucilage from the seed,
some scientists believe
that the enzymatic byproduct
of this stage can add
flavor and impact the aroma
and complexity of the coffee.
But hopefully we're
gonna continue to explore
whether or not that's true.
We can find out for ourselves,
but also how far is too far?
If there such thing
as over-fermentation,
how do we know when it's done?
So because the wild
microflora is so dependent
on so many variables: where
you are, how high you are,
what the weather is like,
what direction the
wind is blowing,
what's it blowing
in, the right answer
for how long fermentation
should take is not universal.
It's very individual.
As I mentioned, it can be
anywhere from six to 72 hours.
Those are documented,
but most processes
typically take 12 to 48 hours,
somewhere in that range,
something in the middle.
Some of the factors
that impact the length
of the fermentation time
is the environment itself:
in the air or the microbes,
what's in the soil,
exactly how the
coffee was processed.
I mentioned all of
this stuff already.
Was it washed
before fermentation?
Sometimes it will
have clean water rinse
before the fermentation stage,
which will remove the
lot of the glucose,
a lot of the sugar, so
there will be less food
for the microbes
and fewer microbes.
So that process would, in
my mind, likely take longer.
How, and if the tank
was cleaned, if the
water is recycled.
A lot of times, the water that
passes through the depulper
will go into the
fermentation tank,
will ferment for 12, 48 hours.
That water will be pushed
back through the depulper
for the next batch,
fermentation tank,
back through the depulper.
So the water, the fermentation
water is being recycled,
and so as it goes, it's being
inoculated over and over again
with more and more yeasts,
bacteria, filamentous fungi.
So that coffee is going
to process differently
as you go and have this
inoculated fermentation water,
and more sugar.
It's gonna be supersaturated
with sugar as well.
And agitation is the last one.
You can agitate the
tank with a paddle.
A few slides ago,
we had the paddle.
And some people stir
it, which of course,
is going to make that go faster.
And there are various
sort of nonscientific ways
for producers to test if their
coffee is done fermenting.
And since the goal
of fermentation
is just to remove the sticky
fruit, or the sticky mucilage,
you would think it'd be
really straightforward
to be like, oh, it's done,
but I think it's common
for people to leave
and come back and
go, oh, it's done.
But was it done three hours ago,
or was it done right
now, kind of thing.
One study that I read in
Nicaragua showed that producers,
I love this story.
In a dry fermentation tank,
or, excuse me, a without
water fermentation tank,
they would take a big
object like a stick,
and stick it in the
tank, and pull it out.
And if the hole remained,
then the fermentation was done.
They're like, great,
everything's, it's now this ...
It doesn't have anything on it.
It's not slippery
anymore, so this is done.
But if the hole
filled itself back in,
then it wasn't done yet.
It needed more time.
So you may be able to consider
some of the pros
and cons of this.
The pro: no equipment necessary.
Grab something.
Put it in the fermentation tank,
and figure out if it's done.
Another pro
is that it's ...
It's like a thing that's worked
for a long time for them,
so it just is this rhythm
that people, I think,
are in already.
A con is that it's
not very quantitative,
as you may have imagined.
So, it can be be
easier to over-ferment.
Not that it's going,
way over-ferment,
this now tastes like
an oniony compost pile,
but it can go a
little past ideal.
And it's also easier
to under-ferment,
which means that you have
some sticky mucilage around,
which is attractive to microbes,
and so you can have
some bad bacteria
sticking around after the fact
and have microbial growth.
So that's what they
were doing in Nicaragua.
So this gentleman here, this
is a photograph from Nurino.
He's holding a
cone kind of cage,
and what they do is they fill
that with the coffee seed,
and then after a
certain amount of time,
and the volume has
reduced a certain amount,
I don't know what
the measurement is,
then they've determined
this is done.
So now they have a
tool, which is great.
Okay, let's talk pros and cons.
So the pro is it's
also inexpensive.
Not as cheap as just
taking something in there,
but it's inexpensive.
It definitely has a more
scientific element to it, right?
It's some form of a measurement,
especially if it's
used consistently.
So that's a benefit.
The con is that ...
It's kind of twofold.
How much reduced is enough
reduced, kind of a thing.
How low of a volume
does it have to be
to be perfectly
achieved, but also,
if you leave this and you
still don't come back to it
for six more hours, was
it done five hours ago,
or was it done two hours ago?
It's no different.
You have to keep
checking in with it,
similar to the
Nicaragua stick study.
So, those are some tools, sort
of low-fi ways of checking
if your fermentation
is complete,
but that study, that same
study in Nicaragua went back,
and they worked to see if it
was possible for producers
to use scientific
instruments on their farms
to determine if
fermentation was complete.
So the first stage of the
study was, is it possible?
Is it practical to
use instruments?
And what that study
found was that pH
was a very consistent
measurement of completion.
Now why?
Because as the Pac-Man
microbes eat the sugars,
and they're releasing
lactic and acetic acid,
the pH is going down.
So a pH reading is telling
you how many of the sugars
have been eaten, right?
How active, how far
along is this process?
So that seemed to be a
consistent measurement for them.
They also found that when
the pH dropped below five,
they determined,
I thought this was
pretty incredible,
and this is one study,
let's keep that in mind,
in Nicaragua, not
very widespread.
They determined that when
the pH drops below five,
fermentation would be complete
in about two hours, clockwork.
But once the pH
drops below four,
over-fermentation
would likely begin.
So now we have a window.
Between five and four
pH, we have this window
of ideal fermentation.
I almost said extraction.
(audience chortles)
And they did find that the
magic number was about 4.6.
So we have a goal.
We had a window.
Now we have a goal that
were aiming for: 4.6 pH.
So why is this helpful?
They found it helpful
because producers
could start planning their day.
They could check in on
the pH of their tank,
and then have some
foresight about when
that tank would be ready
to be washed and moved on
to be dried, which helped
them plan for labor,
for where they need
to be at what time,
which is actually
pretty helpful.
And because pH is a
quantitative measurement,
producers can be more
precise in their execution,
and hopefully
manage their quality
a little bit more closely.
And this also
ended up shortening
producers' fermentation times,
because they didn't need to go
as long as they
thought they did,
as long as that stick told
them they needed to go.
And they also just used
real simple pH strips.
There was no like,
I don't know if any of
you have tested solutions
in pools before, when
you have to drip, drip,
drip, drip and shake it up.
It was none of that, even that.
It's just pH strips, which
is very easy to have around
or in your pocket.
Then they did a second
phase of the study
to look at specifically
if those different levels
of pH were going
to impact flavor.
I don't know if any
of you have done
any scientific research before,
but they had to go in and
see if it was possible first.
And then a few years later,
they then had to write
up another proposal,
and go in and see
what the results were
in the cupping scores,
in the cupping level.
So once they knew they
could implement pH,
they went in and did that study
to see if it could
increase cupping scores.
They were tracking if
you went below 4.6,
if the score went down or if
you were above, closer to five,
if the score was also.
You know, to find where
that exact sweet spot was.
But I'm very sad to say the
results were inconclusive.
They experienced a really
big drop in quality
towards the end of the harvest,
and so they weren't
able, scientifically,
to say clearly if this
was just a quality drop
or if it had anything
to do with pH.
So they essentially needed
to scrub those results,
but the benefit was
that they did get to see
that this was a very
practical thing to be able,
to in the field,
be testing the pH.
So no good news on that front.
So the question
still remains then:
does this fermentation
stage impact flavor?
Most scientists agree
that it impacts aroma.
I kept finding that over
and over in studies,
that fermentation tank
linked with aroma,
and it's because of its
relationship with roasting.
The reducing sugars that
are developed in the seed
come out in the roasting
and then impact the aroma,
which I find interesting.
If I knew more about roasting,
I could probably tell
you much more about that.
So, some scientists believe
that the mucilage
imparts some fruitiness,
whether it's in the aroma or
in the flavor, to the coffee,
but there is no biophysical
study that confirms
that the presence
of fruit compounds
in the fermentation tank
presents itself in the cup.
Nothing conclusive
that says that.
You would think, oh, especially
by the end of the process
there's so many
sugars in that tank
after it's been depulped,
and it's so inoculated,
but there are no, again,
biophysical studies
that say that that's true,
but some scientists do
believe it to be true.
And Tim Hill, our
coffee manager,
he also tends to
believe this, too.
And I don't want
to speak for him,
but he did mention that,
that the mucilage actually
acts almost like a greenhouse
on that green seed,
and it insulates
and protects the seed
from outside influence,
and allows the natural
sugars and enzymes
that are already in
the seed to develop.
So, what is it?
Nature not nurture.
Inside not outside influence
is what people are thinking.
So terroir and all of
that maybe matters more
than what happens in
the fermentation tank.
Internally, the pectins are
fermented into simple sugars,
which then impact the
aroma in the roasting.
Those simple reducing sugars
are brought out in the roasting.
So, again, like I said,
Tim tends to agree,
Tim Hill, that many of
the flavor qualities
are inherent in the seed.
Although, there is
undoubtedly some impact
from the fermentation tank,
it's just tough to determine.
It's just not always
crystal clear,
and not every taster is
able to necessarily ...
taste that.
Aida Batlle, who we work with,
and we're gonna be
tasting her coffees,
she switched a 12-hour
fermentation process,
from in the fermentation
tank for 12 hours,
she switched that to a
24-hour fermentation,
washed it, and then fermented
for another 24 hours.
So she quadrupled her
fermentation time,
and it didn't make
the coffee bad.
Tim said that the
result was more fruited,
but it wasn't wild,
or even off at all.
It was just, had a little bit
of more fruit
present in the cup.
So, I think when we
first approached this,
we're like, if you
over-ferment, that's bad,
and everything goes wrong.
And he's like,
"Whoa, whoa, whoa.
"She quadrupled her fermentation
and everything's fine."
It does seem like that
intermittent wash is helpful,
but at Kamavindi, Tim asked
for an extra four hours
of fermentation time,
which is a 20% increase.
And the reason he asked
for it was in the hopes
that it would sort of mute
the acidity a little bit.
He did mention that in
East African coffees,
acidity can be so
high that sometimes
they benefit from
a little bit longer
in the fermentation tank.
If the fermentation stage
is left way too long,
way too long, the flavors
become more fruited,
as I mentioned, then they
become heavily fruited
with a lower perceived acidity.
Again, this is
perceived acidity,
not thinking about
the pH in the tank,
but in our mouths.
Then coffee starts to
develop almost a gamy flavor.
And finally, it goes into
an oniony or composty,
compost pile sort of a flavor.
So the end result
can be very bad,
but there's a long path you
have to walk to get there.
So, it's not gonna
happen (snaps).
Oh, my pH is 4.2.
Onions.
It's not like that.
There's a lot of wiggle room,
and tasters' preferences
don't always follow science,
and they don't always
follow pH level
in the fermentation tank.
So, we'll find out
a little bit later
how considerable just in the
comparison we're going to do,
how much of a difference
that really makes.
Eco pulper.
Has anyone heard of these?
Yeah, they're really great.
The goal of the Eco
pulper is to be able
to more completely
remove the skin,
the pulp and mucilage
layer of the coffee
in order to reduce or
even completely eliminate
that fermentation stage.
So you don't even have to,
like everything we talked
about just is gone,
which is pretty cool.
I just realized there's
a dog in that picture.
So this can be of huge benefit
where water resources
are limited, right?
Because we're not using a
lot of water for the washing,
although it doesn't take
as much water as we think
about it taking, if they're
recycling it with the depulper.
This can benefit areas where
water resources are limited.
Water savings can be huge.
One manufacturer reports
using just 227 liters of water
per ton of cherries,
as opposed to
20,600 liters of water
per ton of cherries,
used with a traditional
disk pulper.
So, they're claiming like a ...
pretty much like a
20,000 liter increase
without using their machine.
I have no way of verifying that,
but it could be a huge savings.
So any region where
there's not a lot of water,
it could be helpful,
could be more sustainable.
So the question is, well,
why doesn't everyone do it
if it's cleaner,
and uses less water?
They're just really expensive,
like hugely expensive.
Most people who can, most
producers who can afford these
have just such a
large production that
it makes more sense,
because to have these
because of tank space
and for fermentation
and that kind of thing.
So it's just really
cost-prohibitive
for people to use,
as you can imagine.
Sometimes, Tim, again,
our coffee buyer
and quality manager,
sometimes, he prefers
coffees that are eco-pulped,
and sometimes he doesn't.
So it can be great, because
you're just removing
that whole part of the process,
and you don't have much
opportunity for off flavor,
but sometimes you
want opportunity to
mute certain flavors
or create more.
So maybe it's the
wave of the future.
We'll see what
happens with those,
but a lot of people
do use them still.
We just wanted to go through
the stages of coffee processing
and talk about where people
have harnessed fermentation
to change the
coffee a little bit.
At Counter Culture, we
don't use most of these,
but it's interesting
to talk about
because in my research,
these things came up.
Like, oh my gosh,
digestive bioprocessing
came up over and over again.
So coffee cherries.
The coffee cherries
themselves can be digested
and processed by
an animal, right?
Have we heard of Kopi
Luwak or Black Ivory?
Black Ivory's with elephants.
Kopi Luwak is with
the civet cat.
There are obviously negative
and inhumane implications,
and it's very cost-prohibitive,
but people in these ...
These sciences
kept pointing back
at Kopi Luwak as being
so free of acids,
no bitterness, just really
smooth and wonderful,
and so people have developed
processes and enzymes
to reproduce Kopi Luwak without
the civet cat, thankfully.
So it's an interesting
thing that's happening
in terms of using, trying
to manipulate fermentation
and processing for
a specific result.
And then, again, during
mucilage removal,
so if we go from coffee cherry,
to pulping, and then
mucilage removal,
the actual fermentation tank,
something that's happening a lot
is people are
inoculating the tank
with specific yeast strains
for a desired result,
just like where we talked
about with food and alcohol.
The green coffee seeds,
no longer in parchment.
Has anyone heard of
monsooning coffee?
(faint audience response)
Yeah, I think it started
in India, possibly.
Ether way, monsooned coffee
is when green coffee,
not coffee in parchment,
but the green seeds,
after they're hulled,
are left to the elements
of the monsoon rains,
heavy rains, heavy wind,
for three to four months.
True fermentation is likely
happening during that time,
right, because we have
heat, water, and elements.
I think it can be
done in containers,
like actual,
physical containers.
The idea is that the coffee
seeds sort of plump up
and they're washed
of their acidity,
becomes heavier-bodied, and
in very pungent in flavor.
I think some of that
pungency comes from,
I don't want to
say mold or mildew,
without knowing that
that's in there,
but that kind of
sitting around flavor,
sitting around in
the rain flavor.
I don't really know
what that tastes like,
but I can imagine.
Essentially, this process is
reducing any sugar content
left in the green seed,
and then rehydrating
what we already dried out.
So it's kind of
the exact opposite
of what we want at Counter
Culture, for our green coffee.
It's sort of reversing
what we did by washing it,
and drying it, and saving
some of that sugar.
Partially-roasted
and roasted coffee
can also be exposed to
different enzymes and microbes.
There's this thing called
myciliated green coffee,
where a mushroom-derived
enzyme is used
at the green coffee stage
to reduce bitterness
and add nutritional
benefits to coffee.
Has anyone had this?
(faint audience response)
Have you had it?
Our education manager, Emily,
knows someone who's
really into that.
But you can buy it online.
I was looking at it.
It's myciliated coffee.
It sounds really like the
next health-food craze.
But, I mean, any
benefits from mushrooms
I imagine you're
getting from it,
but again, reducing bitterness,
that's something that came
up over and over again:
reducing the
bitterness of coffee.
So, maybe they don't know
that you can buy good coffee
and then extract it well.
(audience laughing)
And then, brewed coffee.
Finally, we get down
to brewed coffee.
I couldn't find
anybody doing anything
to coffee grounds themselves,
but the brewed
coffee, of course,
yeast, lactic acid fermentation
of coffee extracts,
coffee kombucha,
we may have had.
I don't have anyone's had that.
Coffee kefir, that
kind of thing.
A fermented coffee beverage
would be the final stage.
Okay, so the big, the
most interesting thing,
I think, on that list,
the only thing we're
really participating in
is the selected yeast strains.
This is a really fun thing.
I recommend, all of,
pretty much everything
from this slide
came from a podcast
that the SCA put out
with Lucius Solis
and Laurent Berthiot.
I don't know how
to pronounce it.
Any French speakers?
And they are yeast people.
I don't know what you call that.
And they're experimenting
with yeasts with coffee,
but they gave a talk at
SCA in Budapest this year,
and that talk is a podcast
available on SCA's website.
It's really great
if you have an hour.
When you're walking
around or doing something,
listen to it.
It's really exciting stuff,
but we're pretty much just
gonna give you a synopsis of it.
It's called Pulp
Fiction, which is fun.
(audience titters)
Yeah.
We wanted to call
the ProDev that,
but we couldn't rip it off.
Lucio worked in
the wine industry
in kind of the
Napa, Sonoma area,
with Scott Labs, so she
knows a lot about yeast,
but she's wanted to
transfer that to coffee
and coffee producers.
She worked mostly
in the Americas.
Laurent worked in small,
in like a lab setting,
like a small scale in ...
He's from France,
but he was working
with coffees from Africa,
in a much more
controlled environment,
whereas Lucia was
working in the Americas,
heavily influenced
by the producer
and the producers' needs.
Some of them wanted to
increase their cup score,
speed up their
processing, save water,
in one case, slow
down their processing.
So both of them experimented
with underwater,
and without water fermentation.
And something to know is that
when you're working with wine,
you sterilize the wine of all
of the bacteria and microbes,
and then you inoculated with
the yeast strain that you want.
You can't do that with coffee
in the fermentation tank.
So the non-inoculated
ones, there still was wild
or native yeasts on it.
It wasn't completely sterilized,
so they did the testing
with the wild yeasts,
but also versus the
inoculated fermentation tank.
So although experiments like
these are a really good start,
the results are
pretty inconclusive.
We're gonna go through them,
but the potential benefits
are really worth looking into,
because people are doing
this work and claiming
that it's really
going somewhere.
So let's see where it's going.
Increased cup score
and consistency.
The largest score
increase that Lucius saw
was a five point increase,
but that was an outlier.
In general, most
of her increases
were around one to two points.
Our coffee department
urges us to remember
that quality yeast manipulation
is certainly possible,
but five points
is really extreme.
You don't see coffees
really over 95.
So, when we're thinking
about five points
on an 85 to 90, in a
ten-point spectrum,
that's really huge.
Not to say we don't believe her,
but the highest
deviation we've seen
is a two-point difference,
so take that as you will.
Some producers are fermenting
really large batches
in very short amount of times.
Sometime that's
because of temperature,
or because out of
necessity, or whatever.
So selecting appropriate yeasts
helps them elongate
the fermentation time,
which helped them have
better development of flavors
and improved their cup score.
Different yeast strains
produced different aroma
and flavor characteristics,
and that can range from a
clean, crisp, and citrusy
to creamy, funky, woody.
That's used in wine.
In wine you want, you
use certain strains
to produce a specific
flavor profile,
and they are looking to
do that in coffee as well.
The goal is to match
strains with varieties,
to try to bring
out certain flavors
and match them together so
that we get the best result.
It also is great for increasing
the speed of processing.
If there are a lot
of coffees coming
through a washing station, but
you have limited tank space,
and you have a huge harvest,
and you need to
get them through,
otherwise, your cherry
is gonna rot or overripen
on the shrub, you can
free up some space
by improving your fermentation.
If you inoculate more, the
microbes are more active.
and the process can
go a little bit faster
if you do need it to.
You just have to get
the right yeast strain.
Some yeast strains are better
in cooler temperatures,
in cooler climates, and can
help cooler-climate producers
speed up their process so
that it doesn't take so long.
'Cause if you have cold weather,
temperature is a factor,
and you do need it to be a
little bit warmer sometimes
to be faster.
Also, a side benefit
is that it has made
some of her producers seeds
and parchment more uniform,
and prettier.
One of the farmers said that
he's getting a better price now
because his parchment
is pearly white.
That was not something
she anticipated,
but it was this
wonderful benefit.
It's a happy accident.
Also, there's a Q & A at
the end of the podcast,
and a producer
stood up and said,
"I have used yeast, and it
killed the coffee borer,"
In the tank, it was
killing the borer beetle,
and so that was some
benefit that he saw.
Lucia didn't have any
experience with that,
but that shows producers are
using these yeasts on their own
or consulting with
people to benefit,
and that we're seeing
all these side impacts.
This is also new, so we
don't have the full range
of experience yet,
but people are coming together
to kind of work
those things out.
Some variables and
ingredients of fermentation
to think about when it comes
to the inoculation of yeast,
the variety of yeast.
So different varieties impact
different characteristics.
They thrive in
different environments.
So, you can't just go buy some
yeast and hope for the best
in your tank.
If you work with someone
who knows their yeast,
they can help you choose the
right one for your environment.
And as I mentioned, Lucia
wants to build a toolkit
of specific yeast
strains that match up
with specific varieties, so
that people have that resource.
It's pretty easy to manipulate.
Once you know what you need,
you can buy yeasts online.
You just have to make
sure you have enough
so that that yeast
wins the battle,
and that's the yeast
that's taking over
and eating the sugars.
And, again,
we're not able to
kickback the natural flora
and then inoculate
and choose exactly
the one we want.
We have to work with the
wild flora and get a yeast
that works well with that.
The biggest cost
has been shipping.
The yeasts themselves
aren't terribly expensive,
but shipping to Rwanda
is not always cheap.
The fermentation ratio
is also important.
The ripeness and amount
of cherry in the batch
dictate how many
sugars are available.
So, if your cherry
isn't quite as ripe,
there won't be as many sugars.
So, there are all of these
variables to consider,
and also how many cherries
you have, more sugar,
and more mucilage to eat.
The concentration of the yeast
is important, as I mentioned.
Then there's also the
length of fermentation.
With selected yeasts, the
longer the fermentation,
the greater the impact
on the flavor and aroma
is what Lucia's research found,
that the longer it went, the
more flavorful it became.
Her experiments were
mostly 12-, 36-,
and 48-hour fermentations.
She helped a guy go
longer than six hours,
and she helped another
guy go shorter than 72,
so she was sandwiching into
that nice middle ground.
Water is important.
Underwater fermentation,
she found tends
to be more consistent when
you're inoculating the yeast,
because the yeast have
something to travel in,
and so they can approach all
of the coffee
seeds more equally,
whereas un-inoculated
fermentation,
our coffee department
believes is more powerful
when you ferment without water,
because without the
yeast inoculation,
the water just sort
of dilutes the process
a little bit more,
and it happens more intensely
when it's without water.
Does that make sense?
Yeah.
The fermentation vessel,
again, is important.
The tank could be manipulated,
but it's very expensive
and time-consuming to rip
out someone's existing tanks,
put in new ones.
Stainless steel is an easier
environment to control
because it's easy to clean.
It's easy to seal, but it's
also extremely expensive.
So coffee producers likely won't
go the route of winemakers.
Producers, more than likely,
have plastic, ceramic, or tile.
Lucia says a tank you clean,
a concrete tank you clean
is better than a stainless
steel tank you don't clean.
So for her, she wants it
to be a clean environment,
which makes sense,
coming from wine,
when she's used
to sterilization.
For her, cleaning the
tank was important,
just to help ensure that
those inoculated yeast strains
are definitely gonna win
the Game of Thrones
battle to survive.
So the way we at
Counter Culture intend
to start using yeasts
to improve fermentation
is really just so that it
cleaner and possibly quicker.
This question came up of like,
"Are we inoculating coffees
in the fermentation tank?"
And we are gonna taste
some that we have
been able to make available,
but this isn't something we
are wholeheartedly adopting.
You won't see the lactic
acid kind of thing
on our menu right now,
because mostly, we're
thinking about it
as a way to improve
the processing,
not thinking about it as much
from the flavor perspective.
As we learned earlier, that
most scientists believe,
and also Tim Hill, our
coffee manager believes,
that what is inside
the seed is what
is actually
impacting the flavor.
So, he posed it to me
pretty interesting.
It's like, either
the yeast is helping
to remove the mucilage
or it's somehow penetrating
into the seed and changing
the internal structure
and content of that seed.
And if you think about
it in those terms,
it makes more sense to me
that it's just
removing the mucilage
a little bit more effectively,
and in a more controlled manner.
I'm not saying that I don't
believe Lucia's experiments
and Laurent's experiments
and their results,
'cause they obviously have them,
but if you think about it,
everything that we've tasted,
there is actually
fermentation and yeast
in the final products.
Whereas in coffee,
that's not the truth.
There's no actual yeast
in our final product.
Tim is traveling
to France this year
to do more research
with Scott Labs,
and to learn more about
yeast and fermentation,
because we want to know:
is this really happening?
Is this really possible?
If the mucilage is, and
the fermentation tank
is really just making
the greenhouse effect,
then it doesn't make sense to us
that certain yeast
strains are going
to create pineapple
flavors in our coffee,
but hopefully we'll find out,
'cause we have some
yeast-inoculated coffees,
So I don't know yet.
I haven't tasted these coffees.
So we'll see if we can notice
any flavor differences.
And who knows, maybe it could be
from the time the fermentation
took and not so much
from the specific yeast strain.
I don't know, that's
just a thought.
Cool.
Time to taste.
So we're going to
do two tastings.
The first one is going to
be Kilimanjaro three ways.
Right after we taste that,
we're gonna go straight
into this Brazil tasting
of actually inoculated
fermentation.
The first one is spontaneous,
meaning it's using wild, native
yeasts, nothing different.
And then two different
yeast strains inoculated.
(tasters chatting and laughing)
You're welcome to
follow these gentlemen,
right behind them, and
take in some wet aroma.
(deep inhalations)
(low murmured chatter)
- [Male] They do.
(overlapping chatter)
- [Miranda] Thoughts about
this side of the table?
So we got sort of our wild
yeast, un-inoculated control
versus the two inoculated
strains of yeast.
Thoughts about those?
Did they taste yeasty to you?
- I liked it like that.
- No?
I thought they tasted yeasty.
I don't know if it
was like a brain,
again, like trick,
but you didn't taste
like that to you?
Okay.
- No.
- [Miranda] What do you
think about the acidity?
Did the acidity change
at all, or was there
more of a flavor difference or--
- A little more acidity to me.
- Okay.
- Yeah, I thought this
one was the sweetest
of the three.
- The sweetest?
Did have it have anything
stand out as being,
I mean, it's Brazil so
it's a little bit more--
- It's more creamy a
body than that, too.
- [Miranda] Mm-hmm.
- I thought the center
one was the most smooth
of the three on this side.
- Okay.
So the tasting notes
I have for these
from our coffee department:
the first one is walnut, sweet,
slightly bitter, dry.
The second is nut,
mild fruit notes,
and soft mouth feel.
And the last is walnut,
sweet, less sharp.
- [Female] That's
about that one?
- Yeah. Yep.
(muffled chatter)
So there you go.
I felt like there was
a flavor difference,
but I'm having a,
maybe it's because it's outside
of what I normally
taste in coffee.
I'm having a hard
time pinpointing
or identifying
exactly where that is,
but it was almost
more clear to me
on the other side of the table.
But there was a flavor going
on that was a little bit new
or different to me.
I mean, think about on
this side of the table,
it's like, 24 hours in,
then a clean water soak,
and then there are
all of these ways
you could put that together
to create something
that works for
you as a producer,
that works for you
as a coffee-buyer,
that tastes the way that
you want it to taste.
And add in yeast inoculation,
and then there's a
whole nother level
where you can customize this
part of the process to work.
What does fermentation
taste like in coffee?
It's not a linear path
where we can say this,
and then this, and
then this, always.
Again, it's gonna
be up to the taster,
the producer, depend
on the coffee,
where it's grown, what it
tastes like inherently.
But it's not the
same as it translates
in true fermented foods and
fermented products, right?
I did not taste any vinegar
on the table, thank God.
But the coffee industry is
starting to push this potential.
These are all kind of
new ideas, new things
that are happening.
Now, adjusting your process
in the fermentation tank
isn't necessarily new,
but taking the
quantitative measurements,
adding yeast strains,
all of that is new,
so keep your eyes peeled
for more information,
new coffees on the horizon that,
and please, listen
to that SCA podcast.
It's an interesting listen if
you're on a hike or something.
And it's all ultimately
up to the taster, I guess,
whether or not you can
perceive those differences,
and if you care for them.
Happy to answer any questions
you might have lingering.
Our next ProDev, I'm
very excited about.
It's about Ethiopian
coffee varieties.
Instead of saying
Ethiopia heirloom,
as this blanket term for
thousands of varieties
of Arabica coffee in Ethiopia,
we're instead looking
at trying to ...
What's the word?
Verify and identify what those
are, at least some of them,
so we can be more clear
about what we like
in these Ethiopian coffees.
So, we're going to
be exploring that.
Hopefully including Getu,
our member of our team
who lives in Ethiopia,
who is also a botanist
working on his PhD
and to help ...
And part of that process,
for him, is to help identify
these Ethiopia heirloom
coffee varieties.
So we're gonna go
deep in Ethiopia,
probably taste some
phenomenal coffees.
I can't wait.
So, please come back for that.
Spend time, put it
in your calendar.
- Already did it.
- Done.
Got it, great.
So, I really appreciate
you all coming.
Thank you for tasting
coffee with us,
and for being open
to hearing more,
and learning more, and
hopefully you have questions.
Hopefully, you can go
back to your jobs or lives
and be thinking
a little bit more
about fermentation and
how it impacts coffee.
So, thank you for being here.
- Appreciate it.
- Thank you.
