PIA SORENSEN: So welcome, everyone.
So today is fermentation
day, fermentation week,
which is one of my favorite
weeks in the semester.
I also on the side teach a class
on fermentation, so I love this.
And we're very excited to
have Tara Whitsitt here.
And I'm going to introduce
her and leave over to her.
I usually like to start with
this slide because it is such--
and the question I ask, but you
already know the answer to this,
is what do these foods have in common?
But even if you know
the answer, I think it's
worth it to just pause
and look at this and see
just how diverse these flavors are.
I mean, everything from coffee,
chocolate, wine, olives, beer, miso,
yogurt-- really diverse
foods, really diverse flavors.
But they all come from fermentation.
And soon, I think-- I
see some cabbage here.
Soon we're going to turn cabbage
into something really flavorful.
So they've all been produced with bugs.
And I usually-- another
reason I like this lecture
is because so far in this
class, for those of you who
have been coming
earlier in the semester,
so far we've basically cooked the egg.
Sometimes we joke that every
concept that we cover in this class,
you could only talk about eggs.
This entire class is about eggs.
And so so far, we've cooked the egg.
And we've cooked other things than eggs.
We've cooked steak and ceviche,
molten chocolate cake, pesto.
We've whipped egg whites.
And what these have in common
is that they are all ways
that we mess with proteins.
And proteins are basically--
they're the basis of life.
So here, we mess up proteins by heating.
Here we mess up proteins
by adding ceviche,
although this actually looks cooked.
Here, we mess up proteins by
heating the molten chocolate cake.
If we want to make sure that
pesto does not turn dark,
then we want to make
sure that we mess up
the proteins that would turn it dark.
So we would add some acid,
or we would blanch the pesto
before, the basil leaves before,
to make sure it stays green.
Even when we whip egg whites,
we're kind of denaturing.
By physical force, we're
denaturing the proteins.
So we mess with proteins.
What happens when you
mess with proteins?
You kill things.
So this class so far has
just been about death.
It's just been about death.
Now we've come to the
part of the class where
it's about life because now these bugs,
we want to make sure they stay alive.
And we want to make
sure they're super happy
so that they can produce all
of these molecules for us.
So when raise our dough,
when we start our sourdough,
we want to make sure that the
bugs in there are super happy
and they're cranking out
lots of flavor molecules
and making the food delicious.
So it's now about life.
This is a greeting from Michael, who
sometimes does this introduction.
You should look at this, Tara.
He was very excited to
show you this picture.
This is yeast.
He made his own yeast.
TARA WHITSITT: Lovely.
PIA SORENSEN: Lovely.
No, I know.
TARA WHITSITT: Yeah.
PIA SORENSEN: Beautiful.
With bugs, we mean everything
from lactic acid bacteria
to baker's yeast to fungus, which
I know some people-- you know,
it's one of those words
that make you feel
like maybe things aren't so delicious.
But we like to talk straight here.
So these are the kinds of
bugs that we're talking about.
And these are the kinds
of enzymatic reactions
that happen in the bugs that crank
out all these flavor molecules
and molecules that makes things savory
or acidic and makes the food preserve
or, like this picture,
makes us intoxicated.
And basically, what all of these
bugs do is they turn long molecules,
large molecules, into small molecules.
So they take the long sugars, the
long proteins, the long lipids,
and they turn it into ethanol,
gases, aromas, flavor molecules.
They're all smaller molecules.
And the reason they do this is basically
to beat out all the other microbes.
So if you were sitting
here, and you were
producing all these molecules
that smell bad and stink,
then you would want to get out of here.
And maybe you would even, if you
were a microbe, you would die.
And so then all of you would take over.
And you would-- I don't know.
You would make cheese or sauerkraut.
That's the basis of how it works.
This is all part of the chemical
warfare between microbes.
So by producing some of these molecules
which are toxic to other molecules,
you're sort of making sure
your species survives,
and that is ultimately
preserving the food.
OK.
So just quickly, alcohol
is an example of this.
Once you increase the
ethanol concentration,
you can't have so many other
kinds of bugs live there.
Cheese is another example.
It turns out cheese rinds
are these beautiful examples
of biofilms of bacteria.
And Rachel Dutton, who used to
be at Harvard until recently
and is now at UC San Diego, she
actually used cheese as a way
to study and understand
microbial communities.
So she went all other world,
took little cheese samples.
It was a very delicious trip.
And she then sequenced
all of the microbes.
And this is a map of what she found.
This is the amazing
diversity of microbes she
found in cheeses all over the world.
OK.
Fermentation is very close to rotting.
If things go bad, then
you're spoiling the food.
And here is some beautiful
artwork for this.
I'm just going to show you this.
Lovely, beautiful.
This is sort of the bad side.
So real quick, the way this happens
is by exponential growth of bacteria.
So you all know that the way life works
is that you start out with one person,
and it divides and
turns into two people.
And the first person dies.
And then they turn into two
people each, and they die.
And then it goes on like this.
And this is how life works.
So if you were to take this and you
would just turn it into an equation,
you would get this equation.
[APPLAUSE]
Thanks.
Equation of the week.
We clap for equations here.
Yeah.
So you could take this
equation, and you could turn it
into this equation, which is
a little more straightforward.
So I like this one better.
You don't have to clap again.
So you could now look at this
equation, and you could plug things in.
So you could say, OK.
How about I have a piece of
cheese or I have some food.
And there's one salmonella
bacteria on there.
And then I let this thing
sit out for 12 hours.
How many salmonella
bacteria would there be?
So you would plug this
into the equation.
And you would get 7
to 10 to the 10 bugs.
This is 10 zeros.
It's a lot of bugs.
If you did this for 7 grams of
bugs, in fact, that's a lot.
If you did this for 24 hours, then you
would have 10 to the 11 grams of bugs.
So lots of bugs.
Why does that not happen when you
start out with one salmonella bacteria?
Why do not-- I mean, there's got to
be one salmonella bacteria out there
somewhere.
Why is not the Earth taken
over by salmonella bacteria?
AUDIENCE: Growth conditions?
PIA SORENSEN: Growth conditions.
I mean, at some point, they can
only divide as long as there's food.
And as soon as they run out of food,
they're not going to divide anymore.
So lucky for us, usually
they run out of food faster.
So even if the thing-- you know
that sandwich you had earlier today.
Even if there was one
salmonella bacteria on there,
you're probably fine.
You're probably not going to get sick.
And if you do, this is why.
OK.
So that's all I have to say.
So I'm now going to introduce
Tara Whitsitt, which
we're so excited to have her visit.
Tara has a truck.
She has a fermentation truck.
I mean, do I need to say more?
And I'm just gonna leave over to you.
Please, let's welcome Tara.
[APPLAUSE]
TARA WHITSITT: Thank you.
Well, first of all, I want to thank
Harvard for having me here today.
The last time I was in Boston, I was
here with my bus, my 40-foot bus.
And I have a much more lavish
situation this time around being here,
which I never expected to be
in Boston, treated so well.
So yeah, I'm really
grateful to not be parked
on a busy street in
Jamaica Plain getting
very little sleep before speaking
to people about the things I love.
So yeah, thanks.
In October 2013, I departed from
Eugene, Oregon, my home base,
with a 1986 International
Harvester military bus
while slowly converting it to a
fermentation laboratory, library,
and classroom.
I didn't do the entire
installation on my own.
I did it with the help of many
people throughout the United States
over the course of two years.
In those two years, I held 156
events in 27 different states
and reached over 5,000 individuals.
My original goal was to complete
a year-long tour of the United
States called Fermentation on Wheels, in
which I would work at farms in exchange
for food and educational
resources and visit cities
to hold free workshops on
fermentation methods using locally
harvested foods to give people the
tools to consume foods more thoughtfully
and also provide communities with
a direct line to their food source.
It was also to inspire people
to get back into their Kitchens.
It was a challenge.
A lot of friends and family
thought I was kind of losing it.
I was an inexperienced bus driver.
The day I bought my bus was
the first day I drove it.
I had a failed Kickstarter.
My bus had no plumbing or
electricity when I took off.
Over time, my bus has become one of
the most innovative and interesting
learning spaces, but it took
a lot of time and effort.
The very gradual installation
of my solar system
is a good example of
this time and effort.
I began installing my solar system
while I was in northern California
at the Solar Living Institute.
The labor and installation
of fundamental parts
were offered in exchange for letting
a class demonstrate on my bus.
Four months later, in
Mississippi, I made
$500 in donations, five
times the most I'd ever made
in donations teaching fermentation.
So I bought a $250 solar panel.
I had no skill to install
the panel on my bus.
So that was kind of an
obstacle to actually getting
the system working right away.
But nevertheless, I drove with
my panel on the floorboards.
I was patient.
When I parked and taught,
I would drag the panel
to the back of my bus in my
bedroom and hide it, and then
drag it back out when I drove again.
And then a month later, in
Charlotte, North Carolina,
I met two guys that installed
the panel on the roof of my bus
in exchange for sauerkraut.
And this just really proved
the unprecedented generosity
of others and the constant community
of people who want to heal the world
and help others.
And community has become
increasingly important to Americans
over the past decade.
In a country where profit
over people has crept into
and now defines aspects
of our culture, and we're
discovering we may leave the
Earth in worse condition than when
we came to it, we realize more
and more that the only way
to repair these damages
is to work together
for bigger and better outcomes.
At a workshop in Philadelphia in
May, 2014, a local community gardener
and youth educator expressed she felt
the need to do all of the things.
It was overwhelming-- how to
teach others to grow food;
how to get the most out of their food,
whether it be raw, cooked fermented;
and then educating on
thoughtful consumption.
She didn't list these
details, but I knew
exactly what she meant when she felt it
was impossible to do all of the things.
And her end point was, I'm really
glad that you're tackling this issue,
fermentation education, and that you're
making it more accessible to people
all over the nation.
Like, oh, good.
Someone's got that.
And it's impossible to
constantly feel encouraged
when we don't work together to tackle
these massive issues in education,
food, and health.
When I first entered the work world, I
got a corporate job in New York City,
not because I wanted to, but I
didn't think I had other choices.
It had been ingrained in me to take care
of myself and let the rest of the world
take care of itself.
But after five years,
it was a slow transition
leaving my consumer-driven and
small bubble of a lifestyle,
but it began with the desire for change.
Even if I haven't joined
a physical community
in making change in the
world, I was feeling synergy
with the active force of humans
advocating for better food.
And I began that change
first by buying better food,
consuming more thoughtfully.
And I'm not talking about
going to the grocery store
and looking for labels that say
non-GMO, organic, low fat, local.
I'm talking more about actually
reading the back of a package
and seeing if you understand any of
the ingredients listed on the back,
or if you can pronounce
all the ingredients,
which I'll admit there
are a lot of ingredients
I know I can't actually pronounce.
Or you could also just
skip the grocery store
and go to the local farmers
market and buy raw ingredients
from a farmer that's
in the local vicinity.
And so then my next step to fully engage
in a better, more sustainable food
system is to make my meals at
home, to preserve my food at home.
It's empowering, and this
made me feel in unison
with a time passed, with the
original homesteaders of America.
And in some ways, I felt
already for an apocalypse.
And my bus has actually
survived two apocalypses.
They each happened on
Halloween, 2013 and 2014.
Fellow survivors packed into the
bus to admire my healthy compost
pile, clean water, vintage
bus-made wine, sauerkraut,
and a modest exhibit
of fresh vegetables.
My post-apocalyptic bus larder
cleared the motto "YOLO-- You Only
Live Once, ferment your vegetables."
So today, as a 29-year-old who has
circumnavigated the country teaching
people of all ages and socioeconomic
levels in my 40-foot bus
turned laboratory and classroom, filled
with glass and bubbling concoctions,
I remind people
happiness and self-reward
doesn't come from a paycheck
at the end of two weeks.
The most rewarding thing we
can do is follow our dreams,
no matter how terrifying they are.
And my hope is that most
of our fellow dreams
will align with changing the world we
live in now to a world with healthier
air, humans, soil, and water, to promote
a community of thriving organisms
on small and large scales.
Something some of us don't
realize or maybe take for granted
is that all of these things in our
environment-- small and large--
depend on each other for survival.
Understanding my environment and the
food within it as a community project
made fermentation a revelation for me.
I didn't grow up with fermented foods.
The only thing that may have closely
resembled something fermented
from my youth was pasteurized yogurt,
which is not that tasty and lacks
in over half of the nutritional
content it once had.
So why, for the past 60 years,
have we chosen food devoid of life
rather than the real deal?
The true value of food isn't
realized, and it desensitizes us.
Some of our palates don't
understand the real deal anymore.
And luckily, in my
travels, I've now have
the pleasure of tasting dozens
of different yogurt cultures,
each with their own distinct flavor,
all in varying levels of mild to tangy,
and each with their own story, too.
So fermentation celebrates uniqueness.
In addition to our palettes
newfound confusion to uniqueness,
we've been told bacteria
isn't good for us,
even though we're composed of
10 times more bacterial cells
than we are of human cells.
We're 90% microbe.
And good food is not expensive.
In an agricultural system
that is mostly crop
dusted and/or genetically modified
and rotates only between corn, soy,
and sugar beets, real food grown
in healthy soil is a rarity.
The stuff that's widely available,
watered down, and subsidized is cheap.
It's up to us to make positive
consumer decisions that
will ultimately discourage monoculture.
So I urge you to consider
the importance of diversity.
And this might seem super
obvious to a lot of us here.
But access to good
food and food education
is still a huge struggle
for a lot of people,
even for those in nearby
thriving food communities.
For example, the average
household in Princeton,
New Jersey makes three times
that of the family household
in Trenton, New Jersey, where
less than 50% of students
graduate from high school.
Both cities are located in the same
county, and they're 13 miles apart.
Yet Princeton has
historically had access
to good food and top-notch education,
while Trenton falls far behind.
That's changing, slowly but surely.
And part of that is thanks
to a nonprofit called Isles.
Isles, Inc helps members
of the communities
start their own cooperative
gardens and teaches
youth in public schools
about food through gardening.
This is a small fraction of the work
they do to enrich their community.
I was honored to collaborate
with Isles and share
my bus with near 100 students in the
Trenton public school system in 2014.
And they've been a super
valuable partner of mine,
helping reach students who
might otherwise be overlooked.
Isles, Inc is a great example of
the ways in which we can plant seeds
in our communities to make change.
We can plant these
seeds in smaller ways,
too, by simply sharing
and empowering techniques
at home with our family and friends.
Four years ago, a new friend
from my local Brooklyn farmer's
market brought cabbage
and salt to my apartment
and showed me how to make sauerkraut.
I was at awe, not because I was
especially crazy about sauerkraut.
I liked sauerkraut, but I
love meditations in food.
And fermentation was still a
mysterious meditation to me.
It was actually super easy, and it
didn't require a lot of kitchen tools.
And, you know, something
about today's modern kitchen
is I think we feel we need this
overwhelming amount of tools
to actually make a
yummy meal or especially
to preserve something at home.
But it wasn't immediate that
the revelation came when
I packed the sauerkraut into the jar.
It was as the days passed, and I
watched the community of bacteria
in my sauerkraut bubble away.
It's a super collaborative meditation
when sauerkraut begins its process
and you actually watch
the gases begin to rise.
There's a color change, too.
It's a very visual experience.
And so at that point, sauerkraut became
this whole new force in my universe,
and a delicious one, too.
So fermentation has become
my protest to all the things
that disenchant me in the food system.
So that's why I have this huge
monologue on my issues with food
and why it's important to
really recognize diversity
as something we need more of right now.
Fermentation was the
next-level step for,
I feel, changing the way that
we view food in collaboration
with those who tend
the soil it lives in.
We need healthy soil
to get healthy plants
and have rich, awesome
bacteria thriving.
And so I feel what better way to
protest this than to travel the country,
sharing this information for free.
I'm a fermentation
enthusiast, a lover of food.
Some people call me an expert.
I wouldn't say I'm an expert.
I'm an artist.
Accessible education is my medium.
Fermentation is my inspiration tool.
And community is my motivation.
I have been an introvert
most of my life,
but I'm really glad I've
never let that keep me
from standing up for what I believe in.
I refuse to sit on the sidelines.
So with that, let's
make some sauerkraut.
Has anyone here fermented before?
Are people fermenting in this crowd?
Some people.
Who's fermenting vegetables?
Great.
And who is fermenting with starter
cultures, such a sourdough, water
kefir, kombucha?
All right.
Great.
So fermentation is a simple,
naturally-occurring process
where there's a microbial transformation
in which unique flavors are produced,
super tangy flavors, especially.
And what's actually
happening in the process
is sugars are being converted into
acids, gases, and sometimes alcohol.
In this process, we are working
with lactic acid bacteria.
We're making a simple sauerkraut today.
There are three basic controls
when we work in fermentation.
Temperature is big.
So the kind of range at which we want
to ferment in, I say 68 to 76 degrees
is a really good, ideal range.
Of course, you can give or
take a few on either end.
But the main thing to remember is
that the cooler the temperature,
the slower the fermentation
process will work.
And the warmer it is, than the faster
the fermentation process should work.
So it's good to have a kind of medium
range for fermentation to get it going.
And something else about temperature
being a factor in that when it's cold
and things slow down, this is also
a way to hit the pause button.
So when we get towards
the end of the lesson
and talk about packing the food
away, the way we do that is we
actually put it in a refrigerated place.
Another control is salt. We use
salt in the fermentation process
to draw water from the
vegetables we're fermenting.
We also use it to enhance the flavor
or impact the flavor in whatever way.
Some people like less salt.
Some people like more.
That's fine.
But then, finally, salt
is also very important
because it promotes the growth of
lactic acid bacteria, also known
as lactobacillus.
Time is another control
that we use in fermentation.
The longer you ferment for, the more
development of these tangy flavors,
and the shorter you ferment for,
the milder your sauerkraut will be.
So this is one of the beauties
of fermenting at home,
is that you actually decide
when you take the sauerkraut
off of the fermenter, which
is like this ideal temperature
range is the fermenter, you could say.
And yeah, some people like it
after one week, when it's mild.
Some like it at three weeks.
Then you're getting
a good, tangy flavor.
I really like my sauerkraut
at four to five weeks.
So I like it even a little more tangy.
So pickles-- when we make pickles,
there are a few different ways
to make pickles.
And something I think a lot of
people are a little confused about
is what is a fermented pickle
versus a canned pickle?
And canning is very
different from fermenting.
So when we can foods, we're
heat processing the food.
So obviously, no life can occur when
we heat process any of our vegetables.
And in fermentation, it's
entirely the opposite.
We're actually bringing
more life to the food.
The idea is that you're
doubling the life,
and you're enhancing it, making
it a more microbially rich food.
And so when you go to the grocery
store and you see sauerkraut sitting
on the shelf, that's a canned food.
It's not fermented.
If a fermented food were to sit
on a shelf in the grocery store,
it would rot.
It can't sit for long in that state.
It will keep fermenting.
So when you go the refrigerated
section in your grocery store,
that is an actual live, fermented food.
That's the real deal sauerkraut.
So bacteria is everywhere.
What we're working with today, we
would refer to it as wild fermentation.
We call it wild
fermentation because we're
relying on the bacteria that is actually
on the cabbage rather than a bacteria
that we introduce.
There are times where we
introduce other organisms.
We might say one of the
reasons I would culture
my sauerkraut-- let's say I made
a really great batch of sauerkraut
from scratch.
And because any time you
make sauerkraut is completely
unpredictable from one batch to the
next-- conditions will never quite be
the same.
So let's say I make this
really wonderful sauerkraut.
And the only way I can really
get that flavor profile again
is if I transfer a little bit of the
brine from that kraut to my next kraut.
So it's kind of a way
of transferring flavor
profile by grabbing
some of that bacteria
and bringing it over to your next batch.
That's not the most typical
form of starter culture.
Starter cultures are also like
sourdough, kombucha, water kefir,
anything that you use in
the process of inoculation.
This is just another
form of inoculation.
Some people like to culture
their vegetables with whey.
I'm not an especially big fan of whey.
I don't have a lot of whey
hanging out regularly.
So I'm not psyched to
get whey into the mix.
The one benefit if you use a starter
culture while fermenting cabbage is
it speeds up the process a bit.
But wild fermentation, using
just the bacteria that is there,
is a beautiful thing.
It's really easy.
You don't need anything-- salt,
keep it anaerobic-- so omit oxygen--
and give it time.
Yeah.
So people always ask how
do you know you're not
getting undesirable bacteria?
Like, what is keeping it away?
All right.
Yeah.
So lactobacillus is this super
robust, competitive organism.
And it's actually used
in so many of our--
it is present in so many of
our fermented foods-- cheese,
yogurt, kefir especially,
fermented vegetables.
All of these foods are very safe.
Sometimes you'll get the
growth of white or blue mold.
These molds are not toxic.
You can simply scrape them
off, eat what's underneath.
But a really, really great story I
like to tell in regards to lactic acid
bacteria is one of
Noella Marcellino, who
was a nun and a doctor in
microbiology in Connecticut.
And she's a cheese maker
for many, many years.
And she fermented in
a big, wooden barrel.
And one day, the FDA came to her.
This was, I think, in the '80s.
And they said, this is unsanitary.
You have to stop
fermenting in this barrel
and start fermenting in stainless steel.
And as a microbiologist, you can
imagine she was pretty outraged.
Like, yeah, this barrel
has a lot of history.
It's kind of responsible for the
taste and the uniqueness of my cheese.
I definitely can't switch
over to a stainless steel
vessel for my cheese-making process.
And this barrel was,
let's say, like 60 years
old into the cheese-making process.
So she did this really wild thing.
She made two batches, one in a stainless
steel, and the other in her barrel.
And she inoculated
them both with E. coli.
The batch in the stainless
steel was ruined,
and the batch in the
wooden barrel was fine.
And that was because
the wooden barrel was
lined with lactobacilles
from years and years
and years of having
cheese be fermented in it.
And so that really shows the robustness
of this organism we work with.
There have been no recorded
cases of people getting
sick from vegetable fermentation.
If anything, it's not going to
be good because it's not tasty.
Maybe the ingredient combination
you used just wasn't a great one.
And that's a simple part
of any cooking process.
So that's the same deal.
So we're going to go ahead and
move forward with the hands-on.
So equipment we need--
a vessel is important.
I like glass.
I especially recommend glass if you're
getting started in fermentation.
This is because of visibility.
So you can actually see what's
going on within the jar.
If you're getting a little bit of mold
action on the top of your sauerkraut,
then you know to
maintain, scrape it off.
You can also use ceramic, food-grade
plastic, and stainless steel.
So glass is great because, like I
said, visibility and quantities.
So if you want to make just a quart
or kraut, that's really easy to do.
Not everyone wants to
have a gallon of kraut
at home, especially if they live
alone and don't eat that much kraut.
And then a weight is important.
Today, we are simply saving
the leaves of these cabbages.
And we're going to actually pack
the sauerkraut down with the leaves.
So we won't need a weight.
A weight I recommend more if
you have an even larger vessel,
like if you had a gallon.
And also, my favorite
weights are river rocks.
What I do with the river rocks,
I find the smoothest river rocks,
and I scrub them with water, and then
I boil them for 15 to 20 minutes.
I found this to be the
best tool as a weight.
You can also use a jar that will
fit into the mouth of your jar
and fill it with water.
That's a great weight, too.
Some people like to take a thick
plastic bag, put it over the kraut,
and then fill it with water, tie it up.
That works quite fine, as well.
And then you want something to keep dust
and bugs out-- tea towel, rubber band.
There are these really fancy airlock
systems that you can find today,
and they're kind of like
these plastic twist-ons.
And you have a little airlock.
And what airlocks do is they
allow the CO2 to escape,
but no oxygen can come in.
So that creates less
opportunity for mold growth.
It's really not necessary.
If you want to try it out,
you can find them easily.
Maybe some of you are already
using airlock systems.
And then salt-- I use
unrefined sea salt.
I just get salt from the
bulk bin at my grocery store.
I recommend staying away from salt that
has decaking agents or iodine, anything
that is not simply salt.
And that's part of quality
or using any extra type of ingredients
that could mess with your microbes.
Although, I have used
iodized salt. It worked.
Some people say it adds a
flavor that is unpleasant.
I didn't notice that.
But there are a lot of ways to do this.
But obviously, it's easy to just
stick to pure, pure salt. You
can also experiment with smoked
salts-- pink Himalayan salt.
There are these mineral-rich salts.
They work just as well, too.
So does anyone have questions so far?
Yes?
AUDIENCE: [INAUDIBLE].
TARA WHITSITT: Yeah, so salt
promotes the growth of lactobacillus.
Lactobacillus is special
in that it's a halophile.
So it's a salt-loving organism.
Most bacteria, especially
the undesirable guys
that we don't want
hanging out in here, they
do not like salt, which
is what makes the salt
part of this process very safe.
AUDIENCE: [INAUDIBLE].
TARA WHITSITT: Yeah, it's
like the combination of salt
and acidity keeps the
undesirable organisms at bay.
All right.
So we're going to chop some cabbages.
We're saving these
leaves aside for later.
So I always like to half my
cabbages, and then quarter them.
I just find this is a much
easier way to handle them.
And I'm going to go ahead and do
some chopping, too, because it's fun.
Oh, there's just one knife.
MELISSA: It's in the bag.
TARA WHITSITT: Oh.
PIA SORENSEN: If there are questions
while you guys are chopping,
I don't know if you can
do-- I can't chop and answer
a question at the same time.
But you seem so awesome.
So yes?
AUDIENCE: [INAUDIBLE].
Once you have made fermented sauerkraut
and you put it in the refrigerator,
will it be good for
indefinitely, basically?
TARA WHITSITT: I mean, over time, the
sauerkraut will be a little less tasty.
And you also need to be careful
in how you're storing it.
It's best to store it
under the brine if you're
storing it for very long periods.
Generally, it will last anywhere
from six months to a year.
But some sauerkrauts last
longer than that, even.
When working with kimchi, which has
a lot of garlic and is antimicrobial,
I find that garlic always slows
down the fermentation process.
And I can keep it for much,
much longer in cold storage.
Also, it probably has
something to do with the fish
sauce that's in the kimchi.
I mean, fish sauce is kind
of its own different animal
in regards to fermentation.
It's a year-long ferment.
So that probably helps in preservation,
too, with kimchi, specifically.
Because I can leave kimchi
in a refrigerator for years.
And sometimes it's just better.
I mean, it's like the most amazing,
delicious ferment you'll ever have.
AUDIENCE: Thank you.
TARA WHITSITT: You're welcome.
AUDIENCE: How does the
bacteria in whatever you're
fermenting change day-by-day?
So right when you're starting,
what is that profile like?
And how is that on day three versus two
weeks later versus three weeks later?
I know you said lactobacillus really
battles for the space and takes over.
But what's going on in the process?
TARA WHITSITT: Like, the ascent
of lactobacillus over time?
So the movement of lactobacillus,
it's said that at day 28,
that's where there's a kind of
explosion of these organisms.
That's where they hit a climax.
So if you were to have a kind of graph,
it'd be like week one, two, three.
And somewhere between week
three and four, it's like, boom.
And then four, five, six.
And over time, it kind of dwindles.
And I mean, of course that's going to
vary a lot based on temperature, too.
But that's at the range between,
like, 68, 76 that I mentioned.
It's around day 28,
give or take a few days.
But it does move up into a climax,
and then it slowly kind of moves off.
AUDIENCE: When you drive
your bus around, how do you--
TARA WHITSITT: Sorry?
AUDIENCE: When you
drive your bus around,
how do you feel that the vibrations
of moving all of your cultures
around affects fermentation?
TARA WHITSITT: Yeah.
So some of my cultures
don't like agitation.
Some of them couldn't care less.
Some of them like agitation.
I mean, I'm fermenting anywhere
from 30 to 40 different gallons,
or 40 to 50 gallons of
fermented foods and beverages
at any given time on my bus.
So that ranges from wine, beer, cider to
miso and sauerkraut, kimchi, kombucha.
Kombucha and vinegar,
I have the big problem
in that-- do you want me to pass that?
I have the big issue
that I can never form
a proper SCOBY, which is a Symbiotic
Colony of Bacteria and Yeast.
It's the mother, like the
disc formation that you grow
and you use as the starter
culture for future batches.
So yeah, in my bus, when
it's constantly moving,
I can never get a proper SCOBY, which is
not necessary for starting a new batch.
But it does-- her nutritional
presence really speeds things up.
And it makes the process
faster and easier.
So I definitely missed
that when I was on the bus.
And then also, just the
jostling around of kombucha,
given that it's an aerobic ferment.
That had its challenges, too.
AUDIENCE: Great.
Thank you.
AUDIENCE: If you were going
to make fermented pickles,
would you be going about it about the
same way as you're doing the sauerkraut
right now?
TARA WHITSITT: Yeah.
So with sauerkraut,
obviously, you can chop it.
And you could have thin or thick
slices, and it would all kind of
ferment at the same rate because the
surface area is roughly the same.
However, let's say we're
fermenting radishes or turnips.
If we were going to use the process
in which we're just adding salt,
we would need to chop them very finely
and expose a lot of surface area.
However, whole fermented
radishes are delicious.
And whole fermented
cucumbers are delicious,
which is one of the more common
fermented foods we enjoy.
And in that case, rather
than just putting salt
on the whole vegetable-- I
mean, that wouldn't work.
You wouldn't be able
to actually permeate
the walls of the
vegetables, the cell walls.
So we would make a saltwater brine.
And my ratio for the
saltwater brine, I use
1.5 tablespoons per one quart of water.
And then I pour over the vegetables.
This is not a hard number.
Some people prefer two
tablespoons per one quart.
Some prefer one tablespoon per quart.
As you practice, you'll get to
know the salinity percentage
you like with your vegetables.
It took me a good year to figure out
that 1.5 tablespoons was my sweet spot.
So yeah.
And even the cabbage we're going to work
with now, we're going to salt to taste.
The rough ratio when
we salt vegetables is
one tablespoon per two to three pounds.
That's one tablespoon of
salt per two to three pounds.
But I always encourage people
to taste the sauerkraut,
the cabbage, the salty
cabbage before you pack it
because it's OK to
have less salt. If you
don't have a palette for
the super salty, that's OK.
And even with less salt,
if you have enough brine
to push your vegetables underneath
the brine, then you're going to be OK.
And then one thing to really
stay away from is too much salt.
If you have an overwhelming amount
of salt-- while you're salting,
you taste, and you're like,
oh, that's really salty.
I guess I'll just pack it.
Well, you know it's going to taste
way too salty afterwards, too.
So you'll want to figure out a
solution for making it less salty.
You can dilute it by
adding more vegetables.
You could also add some
water to dilute the salt.
But it's always best to start
with less salt rather than more.
Did I answer your question?
Great.
AUDIENCE: Hi.
This is a two-part question.
Can you explain the difference
between pickling and fermentation?
And then also, I don't know
if you've seen any Portlandia,
but there's a sketch called
"You Can Pickle That."
And they pickle all
sorts of normal things,
and then they start pickling,
like, bowling balls and remotes
and stuff like that.
Has there ever been
any ingredient or group
of ingredients that you
just would not ferment,
that just doesn't taste good fermented?
TARA WHITSITT: Yeah.
Well, between pickling and fermenting--
so all fermented vegetables are
pickles.
Not all pickles are fermented.
And that goes back to kind of the
heat processed, pickling process.
You use a vinegar solution.
Vinegar in itself is a
byproduct of fermentation.
So you do get that tangy flavor.
And that's why you
would call it a pickle.
Pickle is kind of defined by
this tangy, unique flavor, right?
But the only difference is
that that kind of pickle
has no more life involved.
There are a few other differences, too.
But this is the primary difference.
Fermented pickles are teeming with life.
As far as-- I haven't seen Portlandia,
so I'm not sure about the sketch
you mentioned.
But there are definitely some things
that are not so great to ferment.
I'll just say as some
advice to people, if you
want to ferment lettuce
or any other leafy greens,
it will be like a green, mushy liquid.
It's really unpleasant.
Super starchy vegetables, the texture
gets really kind of like gritty,
also unpleasant.
I do one ferment with a
more starchy vegetable.
And it's called sweet potato fly.
It's actually a beverage.
And I slice it up, and then
I wash it for five minutes.
And that's, like, to
get the starchiness off.
And then in that recipe, you end up
tossing the solids, the sweet potatoes.
So then the starchy, starchy stuff
is kind of taken out of the equation,
ultimately.
And it's a short ferment.
But yeah, starchy foods, leafy
greens don't really work that well.
I haven't had trouble with much else.
Of course, I've had a few experiments
that just didn't go that great.
If you ferment with
super dark greens, they
have a kind of chlorophyll
flavor, which is not
super pleasant to a lot of people.
Like, if you're doing just, like,
collards and dino kale and these really
dark greens, it's a flavor
that's hard for a lot of people.
PIA SORENSEN: So I have
a really quick question.
So Melissa is doing a lot of massaging.
What if I'm lazy and I
don't want to do that?
Does it still turn out OK?
Sorry.
TARA WHITSITT: No,
that's a great question.
So we are actually
massaging the vegetables
because we want to get this packed into
a jar, like, ASAP, As Soon As Possible.
And another option would be to salt
the vegetables, walk away for an hour,
and come back to sweaty vegetables.
And I do that.
And then there's like
the other extreme, where
people are, like, using these
pounders to pound their kraut,
and it's super-- it's kind of violent.
They're really getting at the cabbage.
But that's totally normal
in a lot of cultures.
And then in eastern Europe, they make
huge barrels of sauerkraut every year.
And my friends from eastern Europe
talk about how when they were children,
they would jump into these barrels and
just jump on the kraut for a long time.
And that was one of these
nostalgic things for them.
So there are all kinds of ways
to get the job done, yeah.
And then and then
ultimately there's a test.
So Melissa, do you want
to kind of make it rain?
MELISSA: I can't.
It's just getting [INAUDIBLE].
TARA WHITSITT: So this is a
test to kind of see if you're
getting a brine to come forth.
It looks good.
And then secondly, you
can kind of take the bowl,
turn it over to check
if there's a puddle.
And that's kind of the next--
yeah, and there's a little puddle.
So that's a good sign that we're
ready to pack into our jars.
And by the way, this is
a very simple sauerkraut.
Green cabbage, salt. It's great.
But if you like chili,
caraway, say you want
to add even some turnips
into the mix, carrots,
you can slice those up nice and fine
and throw them in and ferment those
with your cabbage, too.
And that's one of my
favorite-- I love red cabbage
with thinly sliced
radishes and some chili.
That's like my comfort
food-- after it's fermented.
So yeah, are we ready to pack it?
Are there any other questions
before we pack into the jars?
PIA SORENSEN: Does anyone have the mic?
AUDIENCE: Yeah.
Yeah.
I had a question about-- have you ever
used a pH meter to measure acidity?
Is there some kind of pH threshold
for, I guess, in this case,
sauerkraut or something?
TARA WHITSITT: The pH threshold
is-- you would know that.
MELISSA: Well, there's an ideal.
I work for a commercial--
a small business that
produces fermented foods commercially.
So there are some pH levels.
For food safety, the pH has to be
below 4.6 because above that level
is a danger zone for pathogens.
I can't remember the
range for lactobacillus.
Our vegetable production manager
would know that question.
But it's, I think, in the
high threes, I want to say.
TARA WHITSITT: The high threes.
Sorry.
But yeah, and that's something, if you
do you want to produce commercially,
you'll definitely-- the regulatory
dudes will be like, get that pH.
And it has to be 3.8, between 3.8
and four point something, probably.
That sounds, like, around--
MELISSA: Sure.
TARA WHITSITT: Any other questions?
PIA SORENSEN: You're going
to stay here all night, Tara.
AUDIENCE: Follow up with the scaling up.
If you wanted to
produce it commercially,
let's say you came up with this great
blend of vegetables that tasted great.
And you wanted to produce it in bulk.
Is there a challenge with
using larger vessels?
Does it scale well, the fermentation?
TARA WHITSITT: Is there a challenge
with using larger vessels?
AUDIENCE: Yeah.
Like if you were just to use the same
recipe and just use a bigger vessel.
Does that change the
fermentation usually?
TARA WHITSITT: I mean, there
are a lot of different ways
to produce on large scales.
I've visited a lot of
facilities all over the country,
and everyone has kind of their
different ways that they do it.
But I mean, ultimately, if you
have enough cabbage and manpower,
the right tools- I mean,
obviously, you want something
to be able to really get in
and massage your cabbage.
You usually want a big bucket.
Some people use Hobarts.
If you're familiar with the
Hobart, it's a baking tool.
So you actually have a big bucket,
and then-- it's for mixing dough.
So you would put your cabbage in and
your salt in, and you would mix it up.
And then you can just pour
that into your barrel.
The most common barrel in
commercial fermentation
right now is food-grade
plastic, 55-gallon barrel.
Some people use stainless steel, too.
Stainless steel is much more expensive.
And some smaller producers use crocs.
And they're realizing
very quickly that they
want to get food-grade plastic barrels.
So there are a lot of options.
But you have to consider
how big do you want to be?
How far do you want to
supply your food to?
Did that answer the-- cool.
AUDIENCE: I'm just curious how much
of the massaging process that we're
observing now is just to extract
the water and how much of it
is-- are we also trying to break down
some of the cell structure or something
or tenderize it in a way?
Or is it just about
getting out the water?
TARA WHITSITT: You
know, it's really just
to extract the water, to
get the brine to come forth.
The difference in, say,
texture that occurs
from how much massaging
happens-- you know, I actually
have never noticed a
difference in texture.
I've had some people who were,
like, really crazy, like rawr!
Just getting in there.
And it was some of the
crispiest kraut I ever had.
And I was really surprised by that.
I thought it would be mushy
'cause he was, like, so into it.
And I was like, whoa, buddy.
You're like really squeezing that kraut.
So, yeah, it's kind of just
to get the brine to come out.
AUDIENCE: And then maybe a follow up.
Is there any danger of things exploding?
Do you have to think about that?
TARA WHITSITT: Yeah.
So that is why my method for
keeping dust and bugs out
is the tea towel and rubber band.
If you were to keep
something on airtight,
there's the possibility of an explosion.
It would take a really long time.
If you're working with
something like kombucha or water
kefir, which actually produces
CO2 at a much more rapid rate,
then you'd be in trouble.
But sauerkraut, most vegetable ferments,
it's a very gradual CO2 buildup.
So you'll rarely have
to worry about that.
But you'll definitely-- if it's
airtight, you'll want to burp it.
It's good to burp it
at least once a week.
So yeah.
But this will help.
AUDIENCE: If you wanted to make kimchi,
what would you add to that mixture?
TARA WHITSITT: Kimchi?
AUDIENCE: Yeah.
So kimchi is it's very similar
to the kraut-making process.
However, you usually
integrate Asian cabbage
of some sort, usually bok choy or napa
cabbage, and then root vegetables,
as well.
Onion is popular as an addition.
And then you make a paste.
And that paste is ginger, garlic,
chili powder, and fish sauce.
This is the traditional style paste.
Obviously, there are a lot of
vegetarian versions of kimchi.
And in that case, you can
substitute tamari for fish sauce.
Or you could just omit the fish sauce.
But it's mostly the paste
that makes it uniquely kimchi
and the addition of root vegetables.
Great.
So we packed this down.
Did everyone see on the screen
that it was below the brine?
Should we-- oh, yeah.
You can see it right there.
So let's just do a little.
I just want to show.
I want the shot of-- it's hard
when you have to lean it over,
because then all the brine
just runs to the underside.
So you can't see it.
And now, can anyone see from over there?
Of course, you can't.
That's way too far.
But anyway, these cabbage leaves are
really great for kind of-- I mean,
so one thing they do is they're durable.
So you can actually kind of
just push them down in there,
and they'll hold against
the walls of the jar.
And the brine will stay
above the chopped cabbage.
And then, if any mold does grow, you can
simply take the moldy cabbage leaf off
and compost it.
And so that's one nice aspect of
using cabbage leaves as a top layer.
I learned this from a
woman in Mississippi who
grew up making sauerkraut in Bavaria.
She's Bavarian.
And she was like, oh, yeah.
This is the method we
used when we were young.
And I've used it ever since.
And this was, like, February, 2014.
So I've been doing it
like this for a long time.
And it's pretty no-fail.
If you're concerned about
getting any mold growth,
those leaves will catch the mold
before your sauerkraut does.
And again, how long do we leave it?
This is why it's great
to ferment at home.
You can ferment it for a week if
that's how long you like it at.
It will be mild.
You can ferment it for three
weeks, and it will be tangier.
And if you like it that way, great.
But it's really, really
good practice to,
in maintaining your
sauerkraut, just once a week,
take the leaves off, take a taste.
If you're like, yeah, that's nice, but
not my thing, then pack it back in.
Let it sit longer.
And then taste it the next
week, and then the next.
So it's kind of nice
just to practice getting
to know your sauerkraut, its movements,
and at what stage you really like it.
Another question I get a lot is how
much fermented food should I eat?
And that question, I mean, it
really varies from person to person.
I mean, if you've never eaten fermented
foods, if it's really new to your diet,
I really recommend that people
just use it as a condiment,
like dress your foods with it.
And it's not like you have to eat
kombucha and then sauerkraut and yogurt
and kefir to make sure
that you're getting
this whole balance of microorganisms.
It's kind of like,
yeah, you can mix it up.
But it's not that you won't get
a full probiotic diet if you
omit one of those things one day.
It's totally about kind of trusting your
body, like anyone's journey with food
and becoming just aware of what
your body likes to consume.
And I eat sauerkraut,
like, out of the jar,
as a large side with my eggs in
the morning or with everything.
Kimchi, too.
But I'm totally-- my
body is, like, really,
super adjusted to fermented vegetables.
So, yeah.
That's my spiel.
I hope you all like it.
PIA SORENSEN: So how about we all clap?
[APPLAUSE]
TARA WHITSITT: Thanks.
