Speaker 1: Hey, welcome to Stuff to Blow Your Mind. My name
Speaker 1: is Robert Lamb and I'm Joe McCormick. In today's episode
Speaker 1: is from the Vault. It's Saturday. Of course, it's Vault
Speaker 1: time as always, and so today we're reaching back into
Speaker 1: June of This one originally published on June of last year,
Speaker 1: and this was our episode about fermented vegetables, about kimche
Speaker 1: and sour Crowd and that whole funky awesome world. All right, well,
Speaker 1: let's the vault is open, the kim Chi rise it,
Speaker 1: let's enjoy. Welcome to Stuff to Blow Your Mind production
Speaker 1: of My Heart Radio. Hey you, welcome to Stuff to
Speaker 1: Blow your Mind. My name is Robert Lamb and I'm
Speaker 1: Joe McCormick, and it's fermentation day here at the Stuff
Speaker 1: to Blow Your Mind Podcast. We're gonna be talking about
Speaker 1: kim she one of my favorite foods of all time. Uh.
Speaker 1: And also later in the episode, just wanted to give
Speaker 1: you a heads up. Robert and I are going to
Speaker 1: chat about kimchi for a while first, but later on
Speaker 1: we're gonna be speaking with a bona fide fermentation expert
Speaker 1: from a Tufts fermentation lab. Her name is Dr Esther Miller,
Speaker 1: and it sounds like she's got one of the coolest
Speaker 1: jobs in the world. Yeah, given the title we went
Speaker 1: with here Kim she a Song of Salt and Cabbage,
Speaker 1: I guess it's a missed opportunity for us to have
Speaker 1: done some sort of um wester Roast themed cold open
Speaker 1: skit about about Kim She. Well, I guess the real
Speaker 1: prince who was promised in the story is the lacto
Speaker 1: basilla s bacteria and and he must come in order
Speaker 1: to rescue the fermentation for the jar is dark and
Speaker 1: full of spores. That's pretty good, But of course you
Speaker 1: know there's some there. There has to have been some
Speaker 1: pickling and from and or fermentation in the wester Ros books,
Speaker 1: because it seems like they were always lengthy descriptions of
Speaker 1: what kind of foods UH actors were eating. Yeah, but
Speaker 1: a lot of it is I think like a classic
Speaker 1: Anglo cuisine inspired, which is is actually very low. Well,
Speaker 1: I don't want to be insulting, I would say at
Speaker 1: least the perception is that it's relatively low on on
Speaker 1: spices and and complex flavors. It tends to be a
Speaker 1: rather bland cuisine, kind of focused on grain meat and dairy,
Speaker 1: all right, But then I do we do have to
Speaker 1: to point out that I guess there was beer, there
Speaker 1: was cheese, there was bread. And that's one of the
Speaker 1: reasons that fermented foods are so fascinating because there there
Speaker 1: are these things that we often forget are fermented, like
Speaker 1: cheese and bread and chocolate, and then we have these
Speaker 1: fermented um you know, staples of various fermented goods that
Speaker 1: you're going to have in your your kitchen. And also
Speaker 1: some of the more um elaborate examples. For instance, uh,
Speaker 1: there's the kivak, which is the traditional Inuit food from Greenland,
Speaker 1: in which little ox, these these little birds are caught
Speaker 1: and then fermented in a seal skin and it's buried
Speaker 1: beneath rocks. There's a great feature on this in the
Speaker 1: documentary series Human Planet that came out several years back
Speaker 1: and was at the time narrated by John Hurt. I
Speaker 1: gotta admit, as much as I love fermented foods, I
Speaker 1: have never tried that one, and a lot of the
Speaker 1: fermented foods that I've never really gotten into, or the
Speaker 1: various kinds of fermented meats and dairy products from around
Speaker 1: the world which are extremely common, though I think fermented
Speaker 1: vegetable dishes such as kim chi have seen more of
Speaker 1: an international renaissance and in recent years. Yeah, I feel
Speaker 1: like when I was a kid, I wasn't as exposed
Speaker 1: to as many fermented foods aside from these obviously fermented foods,
Speaker 1: you know, like they I remember being supposed to sour
Speaker 1: kraud but not really digging it for a long time.
Speaker 1: But but now, well you know, is that is that
Speaker 1: a good or bad? Uh? I'm just I'm just so
Speaker 1: sorry for your deprived childhood. I mean, I I can
Speaker 1: remember loving sour kroud as long as I had. One
Speaker 1: of my earliest positive food memories is actually a memory
Speaker 1: of eating a half sour pickle. Um. Yeah, I just
Speaker 1: I don't know, it's It's always been there for me,
Speaker 1: the love of especially like fermented pickled vegetables so good.
Speaker 1: I think I just had kind of work up to it,
Speaker 1: like some of those strong flavors, like there's some sort
Speaker 1: of German um, oh, some sort of purple cabbage type
Speaker 1: thing that I also didn't have a real strong uh
Speaker 1: attraction to at the time. But all these things have
Speaker 1: grown on me today. I love sour kroud and I
Speaker 1: love Kim she I love exploring the various fermented veggie
Speaker 1: or mushroom items you'll find uh in various cuisines. And
Speaker 1: and my son, who is eight now, he's been pretty
Speaker 1: pretty into all things fermented pretty much his whole life,
Speaker 1: as long as they're not actually spicy. That's where he
Speaker 1: has a little more of a struggle. But ultimately, I
Speaker 1: don't know how much of this is his nature versus
Speaker 1: nurture with him, though, Yeah, I wonder about that too,
Speaker 1: because for minute vegetables, definitely they can have strong kind
Speaker 1: of unfamiliar flavors and aromas that takes him getting used to,
Speaker 1: So I would imagine that having a taste for fermented
Speaker 1: foods is somewhat learned. Though then again, I I wonder
Speaker 1: if there could actually be an instinct or at least
Speaker 1: a slight predisposition that humans would have to find certain
Speaker 1: kinds of smells and flavors associated with vegetable fermentation appetizing,
Speaker 1: since this could be a possible vector to get useful
Speaker 1: gut bacteria and other beneficial microbes that I think there's
Speaker 1: good evidence that a lot of these good microbes do
Speaker 1: actually survive the digestion process and and can help recolonize
Speaker 1: the gut with with beneficial bacteria. And then of course
Speaker 1: having healthy gut bacteria could provide some kind of survival advantage.
Speaker 1: So I wonder it's it's possible. I can imagine that
Speaker 1: there's some kind of instinctual predisposition that animals that like
Speaker 1: humans could have, uh to to find these smells and
Speaker 1: flavors appealing. And another thing I would say is that
Speaker 1: you can contrast the appealing or at least potentially appealing
Speaker 1: smell of fermented foods like kimchi or yogurt with smell
Speaker 1: of food that's rotting due to an unambiguously unfriendly micro
Speaker 1: But in these cases, our visceral reaction to the smell,
Speaker 1: I think it's much different. It's sort of automatic, instinctive revulsion. Uh.
Speaker 1: You know, some people might be grossed out by the
Speaker 1: smell of kimchi or sauerkraut, But I think that negative
Speaker 1: reaction is qualitatively different than the like, you know, hot
Speaker 1: garbage kind of reaction people have to the smell of
Speaker 1: like real dangerous spoilage in foods. Yeah, like the like
Speaker 1: the actual like dead animal smell, which really connects with
Speaker 1: us on a on a primal level, like when you
Speaker 1: smell it, you know it. You not might not be
Speaker 1: able to summon that smell in your head right now,
Speaker 1: but it's undeniable when you encounter it. Um. And now
Speaker 1: I've I've I've read some different things about about kids
Speaker 1: in flavor just through I think virtue of of being
Speaker 1: a parent. I know there's the the argument that you know,
Speaker 1: since a child has a smaller body and is more
Speaker 1: susceptible to the dangers of poisons, that that they going
Speaker 1: to be overly sensitive to certain strong smells or flavors. Um.
Speaker 1: And there's also this angle. I've not done any like
Speaker 1: full research into it, and perhaps this would be a
Speaker 1: topic for the future, but I know that biopsychologist Julie
Speaker 1: Manila has researched the topic a bit regarding uh, you know, uh,
Speaker 1: whether we're born with certain food preferences in mind. And
Speaker 1: she has some work that shows that food preferences may
Speaker 1: be developed in the womb or during very early life.
Speaker 1: So we're talking prenatally and postnatally, involving both the amniotic
Speaker 1: fluid and breast milk. So if I'm understanding it correctly,
Speaker 1: the diet of a child's biological mother can influence the
Speaker 1: child's taste later on. Yeah, that would not be surprising
Speaker 1: to me. I mean, I think a lot of things
Speaker 1: from the from the parents environment can come through to
Speaker 1: the child like that. Um. But another thing you know,
Speaker 1: I'm thinking about with with people's taste for fermented foods
Speaker 1: is that it could be a psychological framing issue. You
Speaker 1: You know, we've talked before about the research showing that
Speaker 1: people you can take the same smell and that people
Speaker 1: might find it appealing if you blindfold them and tell
Speaker 1: them the smell is coming from a cheese, but find
Speaker 1: it disgusting if you blindfold them and tell them it's
Speaker 1: coming from a sock. Uh. For people on a Western
Speaker 1: diet who are unfamiliar with kim chi or with other
Speaker 1: fermented vegetables and find the smell off putting, it's possible
Speaker 1: that it's you know, that it's similar aromas that they
Speaker 1: would find appealing if they just had more of a
Speaker 1: reason to associate them with, say the idea of vegetables,
Speaker 1: because like some of the aromas that come off of
Speaker 1: kim chi can smell kind of cheesy, and that's a
Speaker 1: strange thing to smell coming off of vegetables if you're
Speaker 1: not used to it. Yeah, I've I think I've voiced
Speaker 1: a similar thing with Durian fruit before. Durian fruit, of course,
Speaker 1: is is beloved in many parts of the world, but
Speaker 1: sometimes is less appreciated, certainly in western circles, and I
Speaker 1: think part of that is, like, if my my take anyway,
Speaker 1: is that you approach the Durian as being a cheese
Speaker 1: and not a fruit, then then that's going to dismantle
Speaker 1: some of these associations you you make, because when you
Speaker 1: take in the aroma of the Durian fruit, you might think, well,
Speaker 1: that that doesn't smell like I expect a fruit to smell.
Speaker 1: IM more accustomed to a really sweet smell with a
Speaker 1: fruit or something much milder. But if you approach it
Speaker 1: thinking cheese, then I think you're in a better position
Speaker 1: to enjoy it. Yeah. I think that's a really good point,
Speaker 1: and it almost makes me wonder if there is there
Speaker 1: a certain kind of meditation practice that has been honed
Speaker 1: in order to ready the mind to experience new flavors
Speaker 1: and aromas as pleasurable when you're not used to them.
Speaker 1: I wonder if there is such a thing. I think maybe, Yeah,
Speaker 1: maybe just a general sort of centering of the self
Speaker 1: is probably would probably be helpful in those cases. I
Speaker 1: do want to point out to the in terms of
Speaker 1: Durian fruit, I don't have a lot of experience eating
Speaker 1: Durian fruit, so anytime I have encountered it, I am
Speaker 1: very much I feel like encountering it as an outsider
Speaker 1: to like regular consumptions. So I would love to hear
Speaker 1: from anyone out there who is, like, you know, grown
Speaker 1: up with Durian fruit and how you like, because ultimately
Speaker 1: my whole think of it a cheese and not a
Speaker 1: fruit thing that maybe entirely based as well in my
Speaker 1: situation as kind of a Durian outsider, yeah, I can
Speaker 1: see that. But obviously, I mean tastes that were once
Speaker 1: unfamiliar to us can become very very central to our
Speaker 1: way of experiencing food in the world. I mean, so
Speaker 1: I grew up loving pickled vegetables, but I did not, um,
Speaker 1: I did not grow up with kim chi, and now
Speaker 1: kim chi is one of my favorite foods. I mean,
Speaker 1: if you, if you like, pin me down and said, like,
Speaker 1: you know, uh, if you could only eat one kind
Speaker 1: of food the rest of your life, what would it be.
Speaker 1: I would try to reach for something like, well, something
Speaker 1: that could be served with bon schon, you know, all
Speaker 1: those little dishes like Korean side dishes of various different
Speaker 1: vegetable preparations and kim chi and things like that. That's
Speaker 1: the bulls eye for me. That's like the best thing,
Speaker 1: and it wasn't always there. So like clearly, our orientations
Speaker 1: about food can change as we mature, or maybe I
Speaker 1: shouldn't say mature, just as we go on in life.
Speaker 1: So in terms of just fermentation in general, we'll get
Speaker 1: back more specifically to kimchi here in a bit. I
Speaker 1: was reading a bit about it from fermentation expert sand
Speaker 1: Or Cats. I'm sure he's come up in your research
Speaker 1: as well. Um uh, you know, often cited and had
Speaker 1: written several books on the topic, and sauerkraut king. Yeah.
Speaker 1: Cats points out that if you venture into any restaurant
Speaker 1: on the planet, if you dig into any cuisine, you're
Speaker 1: going to find products of fermentation. And again this includes
Speaker 1: more obvious examples such as you know, the sour krout
Speaker 1: and the kimchi, but it also means bread. She's saladdressing alcohol, etcetera.
Speaker 1: In fact, you know, he contends that it's hard to
Speaker 1: get through the day without engaging with a product of fermentation.
Speaker 1: All right, so we're naming fairly disparate seeming food items.
Speaker 1: I mean, what do bread and cheese and sauerkraut and
Speaker 1: kimchi really have in common? What? What? What is it?
Speaker 1: It is the core process of fermentation. Well, in a nutshell,
Speaker 1: we're talking about the chemical breakdown of a substance by bacteria, yeats,
Speaker 1: or other micro organisms, typically involving uh effervescence and the
Speaker 1: giving off of heat. Most notably, it enables humans to
Speaker 1: preserve food and store it for travel, um or for
Speaker 1: you know, for hard times, and as such it was
Speaker 1: often vital for human expansion into harsher climates. Is something
Speaker 1: a way that you could take your food with you
Speaker 1: and it would survive and be edible when you get
Speaker 1: to your destination, or allow you to to have food
Speaker 1: in a destination that is that is harsher, right. I mean,
Speaker 1: one of the big roles of fermentation I think clearly is,
Speaker 1: especially the fermentation of vegetables, is preserving vegetables and products
Speaker 1: through the winter. The traditional preparation cycle for kimchi involves
Speaker 1: packing it into pots in the autumn that can be
Speaker 1: eaten throughout the winter, I guess throughout the rest of
Speaker 1: the year, when fresh vegetables would be hard to come by. So,
Speaker 1: as is often the case with food traditions, I think
Speaker 1: many forms of fermentation, vegetable fermentation likely followed a path
Speaker 1: of beginning with a mistake and then moving to utilitarian
Speaker 1: innovation as a preservative, but eventually just becoming a taste preference,
Speaker 1: becoming something people liked because it's good. But I also
Speaker 1: wanted to go back to a note you had on
Speaker 1: the idea of effervescence in fermentation. This, this idea of
Speaker 1: effervescence or bubbling. Uh, this is actually one of my
Speaker 1: favorite things about certain kinds of kimchi. It's not always
Speaker 1: like this, but certain kinds of kimchi not only have
Speaker 1: these great complex flavors and pleasing crunch, it sometimes has
Speaker 1: something you don't find in other solid foods, which is
Speaker 1: a palpable taste of carbonation in the mouth. Sometimes kim
Speaker 1: chi can kind of bubble and fizz and zing in
Speaker 1: your mouth while you're chewing on it, the same way
Speaker 1: that a sip of a carbonated drink does. And and
Speaker 1: this is one thing I really love that this bubbling
Speaker 1: property of fermentation is all so what creates. Of course,
Speaker 1: you know the crumb structure, the holes in a loaf
Speaker 1: of bread. But these bubbles are gas given off by
Speaker 1: the yeast in bread as they metabolize the sugar in
Speaker 1: the dough. The effervescent property in uh in kimchi, of course,
Speaker 1: is the is the CEO two produced by the bacteria
Speaker 1: as they break down the sugars in the cabbage. But
Speaker 1: this effervescent property of giving off bubbles or gas was
Speaker 1: actually probably where the word fermentation comes from. It's derived
Speaker 1: ultimately from the Latin word for very, meaning to boil
Speaker 1: or to seethe, and ancient Latin speakers probably would have
Speaker 1: been able to observe that as grape juice sat in
Speaker 1: vats and the natural yeasts turned sugar content into alcohol
Speaker 1: to make wine, it would give off bubbles as if
Speaker 1: it were somehow boiling without an external heat source. But anyway,
Speaker 1: so I was reading about fermentation in a in a
Speaker 1: book called the Noma Guide to Fermentation is written by
Speaker 1: the staff of the famous Nordic Cuisine restaurant. But there
Speaker 1: there are several ways they point out that you can
Speaker 1: define fermentation which are basically all scientifically correct at different
Speaker 1: levels of zooming in the first is that fermentation is
Speaker 1: the transformation of foods by microorganisms. You let the microbes
Speaker 1: do something to the food. The second is that it's
Speaker 1: the transformation of foods by enzymes produced by the micro organism. Specifically,
Speaker 1: what they're doing is they're participating in the chemical breakdown
Speaker 1: of molecules in the food. So they're breaking down long
Speaker 1: starch chains into different pieces of those chains, getting a
Speaker 1: little different sugars and things. They're breaking down long protein
Speaker 1: chains into smaller pieces of those chains. But then finally
Speaker 1: they say it is quote the process by which a
Speaker 1: micro organism converts sugar into another substance in the absence
Speaker 1: of oxygen and uh ands. As we know that there
Speaker 1: are different microbes that are involved in different kinds of fermentation.
Speaker 1: So for example, you've got yeast, which is a fungal
Speaker 1: micro it's a fungus and it's the agent primarily involved
Speaker 1: in the creation of bread, but also wine and beer.
Speaker 1: While the agent most important to the fermentation of vegetables
Speaker 1: like cabbage in sourkroud and kim chi is lactic acid bacteria.
Speaker 1: And we'll get into more detail on that later, but
Speaker 1: the gist is that if you take a bunch of
Speaker 1: vegetables such as cabbage, doesn't have to be cabbage, but
Speaker 1: this is often the vegetable used you put salt on them,
Speaker 1: they'll kind of whilt down, release water, create a brine
Speaker 1: that's salty in nature, and the salt creates an environment
Speaker 1: where certain kinds of bacteria that are tolerant of salt
Speaker 1: can thrive and overtake other microbes which are less tolerant
Speaker 1: of salt. And as they take over, these lactic acid
Speaker 1: bacteria further drive out other biological contaminants with the byproducts
Speaker 1: of their metabolism. In the case of lactic acid bacteria,
Speaker 1: as they eat the sugars and the vegetables and the brine,
Speaker 1: they excrete lactic acid, which of course is an acid.
Speaker 1: It lowers the h of the brine. It acts as
Speaker 1: a preservative, so it inhibits the growth of other microbes,
Speaker 1: kind of like if you had added an acid directly,
Speaker 1: like if you added vinegar or some of their acid
Speaker 1: to pickle your food, except a major difference is that
Speaker 1: the flavors that come out of the bacterial acid production
Speaker 1: process are so much more complex and rich than the
Speaker 1: sort of one note flavor of a simple dash of vinegar. Now, fermentation,
Speaker 1: of course, uh as I think is already coming out,
Speaker 1: occurs without human intention all the time. No humans are
Speaker 1: required for this, and examples range from the fermentation of
Speaker 1: fallen fruit to the interuric fermentation inside a creature's digestive system. Yeah,
Speaker 1: and this is actually an evolutionary adaptation. Interect fermentation is
Speaker 1: really interesting. So it is a symbiotic adaptation involving multiple
Speaker 1: different species working together, and it's used by many animals,
Speaker 1: including ruminant herbivores like sheep and cattle and camels, and
Speaker 1: it allows them to survive on a diet of tough,
Speaker 1: cellulose riddled plant matter that animals like us simply couldn't digest.
Speaker 1: I mean, if you and I go out and eat
Speaker 1: a bunch of grass. My dog tries it sometimes, but
Speaker 1: I don't think it really helps them all that much.
Speaker 1: Um and we we we just would not be able
Speaker 1: to get much energy out of it at all. But
Speaker 1: there's an advantage to surviving on a diet like this
Speaker 1: if you can. Obviously, tough plant matter like grass is abundant,
Speaker 1: it's easy to capture there's lots of it. It doesn't
Speaker 1: run or fight back, but it's just hard to get
Speaker 1: useful chemical energy out of it. So animals with natural
Speaker 1: enteric fermentation use the help of a cultivated microbiome. They
Speaker 1: have chambers in their digestive system specifically for the microbial
Speaker 1: breakdown of tough plant matter, and it transforms all that
Speaker 1: grass and stuff like that into simple sugars that can
Speaker 1: be easily used as energy by the animals. So it's
Speaker 1: almost like these room and herbivores have a kim chi
Speaker 1: jar inside their digestive system. But you know, if you've
Speaker 1: ever tried to make kimche at home, which I am
Speaker 1: doing right now, one thing you know is that as
Speaker 1: the fermentation happens, you either need to have a ventable
Speaker 1: lid on the jar that will allow gas to escape,
Speaker 1: or you need to burp it frequently. You need to
Speaker 1: take the top off and let the gas out, or
Speaker 1: pressure can really build up with some disastrous consequences, which
Speaker 1: we can talk about at a little more later. And
Speaker 1: a similar thing actually goes on with animals that undergo
Speaker 1: terrek fermentation, because these room at herbivores end up having
Speaker 1: to burp out an awful lot of byproduct gas, generally methane, right,
Speaker 1: and in large enough quantity, which is generally the case
Speaker 1: with say cows that are that are that are raised
Speaker 1: by humans, that actually adds up and has an impact
Speaker 1: on climate. Yeah, that's absolutely right, And in fact, I
Speaker 1: know they're ongoing projects to try to fiddle with that,
Speaker 1: to say, like, can we actually get down the level
Speaker 1: of methane that is exhaled by these room and herbivores
Speaker 1: by making certain tweaks to say their gut mic orobiota
Speaker 1: or two there, or to exactly what the sugars in
Speaker 1: their diet are and things like that. So that's cows.
Speaker 1: But when it comes to humans, and specifically when it
Speaker 1: comes to the intentional use of fermentation, of the fermentation process,
Speaker 1: this is widely considered a Neolithic technology. We're gonna take
Speaker 1: a quick break, but when we come back, we will
Speaker 1: dive into what we know of the history of fermentation. Alright,
Speaker 1: we're back. So Robert, you you've teased us about the
Speaker 1: history of fermentation, saying that intentional use of fermentation of
Speaker 1: foods by humans is something that goes back to the
Speaker 1: Stone Age, the Neolithic era, right, you know, at least
Speaker 1: so evidence of fermented beverages in China, for instance, seemed
Speaker 1: to date back to the seventh millennium BC, based on
Speaker 1: evidence from a Neolithic village in Henan Province UH and
Speaker 1: this this evidence revealed a fermented mixture of rice, honey
Speaker 1: and fruit. This was mentioned in um in a in
Speaker 1: a paper titled Fermented Beverages in pre and Protohistoric China
Speaker 1: from P. And A. S. H in two thousand four
Speaker 1: written by A McGovern at all and then I was
Speaker 1: also looking at a two thousands sixteen study from Adam
Speaker 1: Bothius in the Journal of Archaeological Science, and that puts
Speaker 1: a date on Scandinavian fermentation evidence to nine thousand, two
Speaker 1: hundred years ago during the early Mesolithic UH. This would
Speaker 1: have been processed fish, So the idea here is that
Speaker 1: they were using something described as a gutter to ferment
Speaker 1: fish in preserving it for later. The author discovered evidence
Speaker 1: of this gutter along with vast quantities of well preserved
Speaker 1: fish bones to support this argument. And fermented fish products
Speaker 1: are actually very common now you might not know that
Speaker 1: you've been consuming them, but examples include Worcestershire sauce. This
Speaker 1: is a fermented fish product or of course Asian fish
Speaker 1: sauces nonplaw. These are made by salting fish and then
Speaker 1: using the extracted liquid that comes out as the strong,
Speaker 1: deeply complex salty flavoring agent. Another example would be an
Speaker 1: ancient Roman food known as garum, which was actually in
Speaker 1: many many ways similar to Asian fish sauce. So fermented
Speaker 1: fish products are are actually in wide use around the
Speaker 1: world today. You might not always think about them being
Speaker 1: the product of rotting fish but or you know, controlled
Speaker 1: rot but that's what they are. Yeah. And if you
Speaker 1: want more on garam and in various fish fermentation in
Speaker 1: products sauces, we did an episode of Invention about ketchup
Speaker 1: and and how all this ties into the history of
Speaker 1: the product we now know as ketchup. Yeah. Now, as
Speaker 1: for the fermentation of vegetables, that's key to what we're
Speaker 1: talking about here with Kimche And it's believed that this
Speaker 1: too came before the agricultural revolution, so before we were
Speaker 1: able as humans to harness crop technology to control uh
Speaker 1: and manipulate the way crops grow for our benefit, we
Speaker 1: harness the power to preserve those goods through fermentation. This
Speaker 1: is fascinating and it reminds me of the evidence that
Speaker 1: we've discussed previously that the invention of bread probably predates
Speaker 1: the invention of agriculture, before wheat and other grains were
Speaker 1: staple crops that people grew on purpose. It looks like
Speaker 1: we have pretty good evidence that Stone Age people's were
Speaker 1: harvesting wild grains such as iron corn, wheat, grass, taking,
Speaker 1: taking those grains and then baking bread out of it.
Speaker 1: The evidence we talked about was a paper published in
Speaker 1: in p N A s by Iran's oteg we at
Speaker 1: All and basically the authors here, we're looking at an
Speaker 1: archaeological site in Jordan's that was an ancient cooking site
Speaker 1: from about fourteen thousand years ago when they found matter
Speaker 1: that looks very much like breadcrumbs there. So these would
Speaker 1: be bread, predating the agricultural revolution by thousands of years now.
Speaker 1: As for kimchi itself, so yeah, we've already described it
Speaker 1: a bit and talked about it a bit. We're gonna
Speaker 1: do a little more detail here. There are a lot
Speaker 1: of fermentent items out there that we can compare to kimchi.
Speaker 1: But Joe, I don't I don't know if you'd agree
Speaker 1: with this, but I feel like in many ways, there's
Speaker 1: nothing quite like it. Oh yeah, I mean I love
Speaker 1: for minute vegetables generally, but kim chi is in a
Speaker 1: class all of its own. It is a culinary suet Gennaris. Now, Now,
Speaker 1: at a very basic level, what we're talking about here
Speaker 1: is a traditional side dish of salted and fermented vegetables,
Speaker 1: generally something like napa cabbage Korean radish, made with a
Speaker 1: varying selection of traditional seasonings. Yeah, A very common preparation
Speaker 1: for kimchi would be you take napa cabbage, you salt
Speaker 1: it to to begin a wilting process that will bring
Speaker 1: water out of it, and then you prepare a brine
Speaker 1: or a marinade that will be made out of a
Speaker 1: Korean chili flake, often go chugaru, which is a red
Speaker 1: chili flake um. And then ginger garlic, often some kind
Speaker 1: of fermented fish products such as salted shrimp or fish
Speaker 1: sauce uh. And then other other ingredients such as maybe
Speaker 1: graded carrots, scallions um. I might I might be leaving
Speaker 1: a few things out here, but that's a pretty standard preparation. Now.
Speaker 1: I was reading about kimchi in the history of Korean
Speaker 1: go Chu Go go Chang and Kimchi in the Journal
Speaker 1: of Ethnic Foods from And This was by Kwan at
Speaker 1: All and it points out that you know, as you
Speaker 1: might imagine, fermentation in Korea began as a means of
Speaker 1: preserving vegetables. Normally the Chinese cabbage or kimchi cabbage as
Speaker 1: it is known today, it decomposes at normal temperatures due
Speaker 1: to the action of micro organisms. The authors here point
Speaker 1: out that specifically with with modern kim chi, you add
Speaker 1: red pepper powder containing capsation to the cabbage and this
Speaker 1: suppresses the growth of of putrefying bacteria and promotes lactic
Speaker 1: acid bacteria. The micro organisms here the authors where I
Speaker 1: grow and change into a form that emans can consume. Now,
Speaker 1: the basic process here is responsible for other key Korean
Speaker 1: fer minted food products as well UH, such as a
Speaker 1: go go chang, uh, Chian cook chang, and doan jang.
Speaker 1: But one of the key ingredients in modern kimchi is
Speaker 1: the go chu, the Korean red pepper UH. This powder,
Speaker 1: which again is involved in arresting beatification and leads to
Speaker 1: the production of lactic acid. And there are different varieties
Speaker 1: of go go chu. I think they're like four main
Speaker 1: categories now in terms of when the gochu peppers become
Speaker 1: involved in the process, apparently there I was, I was
Speaker 1: not really prepared for this, but apparently there's some back
Speaker 1: and forth about when they actually enter Korean cuisine. Yeah,
Speaker 1: I was surprised to find that there's some kind of controversy.
Speaker 1: It's apparently a somewhat contested issue. Uh that's infused maybe
Speaker 1: with modern political concerns, like when exactly different types of
Speaker 1: kim chi came to exist. Yeah. For instance, that Quan
Speaker 1: paper that I that I had just mentioned, uh in
Speaker 1: that they contend that quote go chu started to grow
Speaker 1: on the Korean peninsula a few billion years ago, and
Speaker 1: it is safe to say it is original to Korea.
Speaker 1: So that's that is very much um uh in disagreement
Speaker 1: with with some of the information we're gonna get to
Speaker 1: here in a second, but I wanted to go ahead
Speaker 1: and put that out there. There's also apparently an argument
Speaker 1: that kim chi is less than a century old, with
Speaker 1: the pepper being introduced to Korea via Japan during World
Speaker 1: War Two, but this is strongly dismissed in many sources,
Speaker 1: including a two thousand fifteen paper by jag at All
Speaker 1: in Journal of Ethnic Foods, citing the Chronicles of the
Speaker 1: Three Kingdoms of Korea as a as an historical source,
Speaker 1: dating kimchi back at least fifteen hundred years in Korean
Speaker 1: culinary tradition. The argument here is that it it would
Speaker 1: have been invented thousands of years ago. Uh, and then
Speaker 1: but bolical, we see it at least some evidence of
Speaker 1: it fifteen hundred years ago. Yeah, based on the historical
Speaker 1: sources I was reading, it seems like the most likely
Speaker 1: thing is that kimchi is definitely an ancient Korean food,
Speaker 1: but the introduction of peppers specifically is more recent. Right, Yeah,
Speaker 1: that seems to be the case that you don't you
Speaker 1: don't need, or you at least didn't need peppers for
Speaker 1: kim chi, uh, you know, throughout most of its history,
Speaker 1: but then you end up seeing the introduction of these peppers.
Speaker 1: I was reading The Colombian Exchange, A History of Disease,
Speaker 1: Food and Ideas by Nathan Nunn and Nancy Kuan, who
Speaker 1: point out that the peppers used here, the peppers alone,
Speaker 1: not the Korean fermentation traditions, etcetera, have a New World origin.
Speaker 1: So uh, these peppers would have originated in areas of
Speaker 1: what is today Bolivia and southern Brazil. From there they
Speaker 1: traveled into meso America and the Caribbean before the arrival
Speaker 1: of Europeans, who then took it elsewhere. So along these lengths,
Speaker 1: it's the Korean chili pepper was probably introduced to Korea
Speaker 1: in the early sixteenth century, and the actual kimchi tradition
Speaker 1: was much older, however, and seems to have its roots
Speaker 1: in Chinese pickling. And here's what J. Bock Park wrote
Speaker 1: about it in Red Pepper and kim she in Korea
Speaker 1: in the Chili Pepper Institute paper from nineteen quote, it's
Speaker 1: thought that kim she may have originated from Chinese pickles.
Speaker 1: These pickles were brought to Korea and we're altered into
Speaker 1: several types of kimchi to suit the taste of Koreans
Speaker 1: during the Sheila and Korea dynasties. That's C through and
Speaker 1: cen through two respectively. Uh. Anyway, the author continues, quote,
Speaker 1: Since red peppers were imported to Korea in the early
Speaker 1: part of the seventeenth century, whole cabbage kimchi and other
Speaker 1: kim she prepared with hot red pepper became popular. Yeah,
Speaker 1: and this matches up with everything I was reading. Uh.
Speaker 1: And and in fact, while go chugaru the red pepper
Speaker 1: flake is a very important ingredient in some of the
Speaker 1: most popular forms of kimchi, I believe there are still
Speaker 1: forms of kim she made that don't involve it, that
Speaker 1: might be known as like white kimchi, that might in
Speaker 1: fact be more similar to the older tradition that would
Speaker 1: of course involve salting the cabbage, it would involve adding
Speaker 1: flavorings to the to the brian or the marinade. But
Speaker 1: would but but don't bring in the hot peppers. Yeah.
Speaker 1: So I know. I do want to stress though, that
Speaker 1: we've only briefly gone over the history here, but obviously
Speaker 1: we've touched on various elements that involve colonial and imperial expansion.
Speaker 1: So I think it's it's it's obvious why uh Sometimes
Speaker 1: um you know, some of these are very impassioned arguments. Um. Plus,
Speaker 1: it seems like it is difficult to overstate just how
Speaker 1: important kim she is in Korean culinary culture. Uh. There's
Speaker 1: a two thousand sixteen article on NPRS The Salt titled
Speaker 1: how South Korea uses kimchi to connect to the world
Speaker 1: and beyond, and it shares the following quote. Kimchi is
Speaker 1: not just cabbage salad. It is essential to the culture
Speaker 1: of the country. There are hundreds of different varieties of
Speaker 1: kimchi and Korea, and about one point five million tons
Speaker 1: of it is consumed each year. Even the Korean stock
Speaker 1: market reflects this obsession. The Kimchi index tracks win Napa,
Speaker 1: cabbage and a twelve other ingredients chili, carrots, radishes, and
Speaker 1: anchovies among them, are at their best prices. Yeah, there's
Speaker 1: been a pretty concerted effort over the years by the
Speaker 1: South Korean government to promote kimchi as a as a
Speaker 1: sort of trendy food worldwide. And I can't you know,
Speaker 1: I can't say I blame them like that. You've got
Speaker 1: you've got this great culinary tradition. Why not use that
Speaker 1: to to help engender love for your culture around the world. Yeah, yeah,
Speaker 1: share it with the world. And that's where you see
Speaker 1: initiatives like the Kimchi bus. I don't know if you
Speaker 1: ran across articles about this, No, I didn't um. This
Speaker 1: was which was supported in some part by the South
Speaker 1: Korean government, and it you know, I don't think it's
Speaker 1: active right now, but it at least was traveling around
Speaker 1: to various countries and spreading traditional Korean food and kimchi. Um,
Speaker 1: you know, very very much spreading the word of kimchi.
Speaker 1: It's like an Iowa campaign bus for kimchi. The kimchi
Speaker 1: is going to get out and give a speech. Now.
Speaker 1: That article from The Salt it also points out some
Speaker 1: other uh cool facts about about the culture of kimchi
Speaker 1: and in related foods. At points out that kim jang,
Speaker 1: the tradition of making kimchi, has long been a unifying
Speaker 1: tradition amid Korean villages and a sustaining one through periods
Speaker 1: of hardship, and that kim jang was even added to
Speaker 1: the UNESCO Representative List of the Intangible Cultural Heritage of Humanity,
Speaker 1: which is pretty impressive. Absolutely so. Again, the kim jang
Speaker 1: would be these, uh these events where people gather together
Speaker 1: to make their their pots of kim chi in the
Speaker 1: autumn that can be buried for the winter or the
Speaker 1: rest of the year. Yeah. Yeah. Based on this article's description,
Speaker 1: it seems like, you know, a sort of a community
Speaker 1: wide or even cross community kimchi making enterprise, spreading the
Speaker 1: labor intensive process out amid a large group of people.
Speaker 1: So it's not just you know, my household is making
Speaker 1: kimchee today. It's no we we as a community, you know,
Speaker 1: or even we as you know, as people are making
Speaker 1: kim che today. Well, you know, I was telling you
Speaker 1: about this the other day actually that, uh, my experiments
Speaker 1: in making kimchi at home have been a solitary project
Speaker 1: so far. But I can absolutely see how making kimchi
Speaker 1: would be a really fun social family and friends kind
Speaker 1: of project. Is something fun to do with the kids
Speaker 1: because like, the kids can maybe work on massaging the
Speaker 1: salt into the cabbage and massaging in the marinade between
Speaker 1: the leaves, and you can talk while you're doing it.
Speaker 1: I mean, it seems like an ideal social food preparation situation. Yeah,
Speaker 1: it sounds fun. You were mentioning the specific jars you
Speaker 1: have for it, and I think we actually have one
Speaker 1: of those jars, because I think we have some sort
Speaker 1: of Sauer kraut kit that just hasn't been used yet,
Speaker 1: you know, we've been eyeing, and so that might it
Speaker 1: seems like that might be usable for this process as well.
Speaker 1: Oh yeah, So to further clarify out there what what
Speaker 1: I had been offering to share with Robert was was
Speaker 1: burp lids for jars, which I got, which allows you to,
Speaker 1: you know, in case you forget about the kimchi you've
Speaker 1: got going in the jar, It's not going to blow
Speaker 1: the lid off or anything. It's got a little vent
Speaker 1: where if the pressure really builds up inside the CEO
Speaker 1: two can escape out the vent. Now, speaking of pressure,
Speaker 1: I spaces. This gets right Intoto. The next thing I
Speaker 1: wanted to talk about here that I know you were
Speaker 1: excited about as well, Joe. Yeah, and that's you have
Speaker 1: something as as culturally important as kimchi. Uh. This is
Speaker 1: one of the reasons that kimchi has gone into space.
Speaker 1: So in two thousand eight, South Korea's Uh sillan ye
Speaker 1: was selected to be the country's first astronaut, and the
Speaker 1: government apparently had worked nearly a decade to create uh
Speaker 1: kimchi as well as other Korean dishes they could potentially
Speaker 1: be taken into space that we're space ready, uh for
Speaker 1: just such an individual. Now, as for why why take
Speaker 1: kim she into space? Well, okay, so there are a
Speaker 1: few different reasons. So one of them, of course, we
Speaker 1: again we've touched on the cultural importance of the dish.
Speaker 1: If you're sending an astronaut into space, that is not
Speaker 1: only a scientific endeavor, it is you know, it's about
Speaker 1: you know, national pride to a large extent, So it
Speaker 1: makes sense to want to send something as important and
Speaker 1: is kim chi up with them on an individual level.
Speaker 1: We've talked about this in the past concerning space food.
Speaker 1: You know that this is um going into spaces physically
Speaker 1: and mentally um you know, exhausting endeavor. So if you
Speaker 1: have something meaningful for them to eat up there, you know,
Speaker 1: some sort of some sort of food that that not
Speaker 1: only sustains them but perhaps reminds them of home, etcetera. Like,
Speaker 1: that's that's that's a win. So there's been there's always
Speaker 1: been an effort to do that with the food that
Speaker 1: is sent up with astronauts. But then on top of that,
Speaker 1: micro gravity often is often described as uh is living
Speaker 1: in microscrap. Gravity rather is often described as being in
Speaker 1: this kind of state of perpetual nasal blockage, right, because
Speaker 1: everything is just kind of you know, without gravity, everything
Speaker 1: just kind of moves up and it just floats free.
Speaker 1: So this is one of the reasons that it's kind
Speaker 1: of difficult to taste food in space, and so you
Speaker 1: want something with a strong flavor, perhaps spice to it,
Speaker 1: if you really want to to to taste anything. And
Speaker 1: that's one of the reasons that NASA's shrimp cocktail has
Speaker 1: apparently been popular for years. Not because people want those
Speaker 1: you know, those shrimp that have been kind of stepped
Speaker 1: on orbit, but it's that it's the horse radish in
Speaker 1: the cocktail sauce, like, it has a strong spicy flavor
Speaker 1: and it can kind of clear your head a bit,
Speaker 1: that's right. Yeah, it opens up those nasal passages. There's
Speaker 1: there's something there you can detect as as far as
Speaker 1: flavor and aroma goes um. But another thing I wanted
Speaker 1: to emphasize again, uh, the idea of a Korean astronaut
Speaker 1: having access to kim chi as part of their food
Speaker 1: in space. This is not just important because obviously it
Speaker 1: is part of Korean cuisine, but that it is such
Speaker 1: a regular part of traditional Korean culinary life, that um,
Speaker 1: that kim chi. You know, it's not unusual for kim
Speaker 1: chi to be served at basically every meal on every
Speaker 1: on a Korean table, right, Yeah, it is. It is
Speaker 1: the the traditional side dish, so you know, it would
Speaker 1: be so in a similar sense. You know, it's like,
Speaker 1: of course there's ketchup in space or some version of it,
Speaker 1: because that is like the staple of some people's diets, right,
Speaker 1: Kimchi is very much the same affair. But the idea
Speaker 1: of taking kimchi into space, well, of course a wonderful
Speaker 1: idea as far as the flavor and the comfort that
Speaker 1: that it can provide, it immediately calls to mind some
Speaker 1: particular hazards in the case of kimchi that are not
Speaker 1: the case with other foods. Because have you ever seen
Speaker 1: what happens when there is a sealed jar of kim
Speaker 1: chi without a burping lid, and the fermentation gets a
Speaker 1: little too aggressive, gets a little frisky. Uh, you should
Speaker 1: look up video of this, Robert. And so the microbes
Speaker 1: inside the fermentation will produce c O two as they
Speaker 1: do their business, and they can produce so much c
Speaker 1: O two that they can basically blow the lids off
Speaker 1: of jars, or maybe maybe if they don't blow the
Speaker 1: lid off when you open the jar, suddenly it's like
Speaker 1: when you know, it's like mintos in a diet coke.
Speaker 1: It's like spewing spicy marinate everywhere, and the cabbage puffs
Speaker 1: up out of the top like you know, a muffin
Speaker 1: coming out of its mold, or like a Yorkshire pudding. Uh,
Speaker 1: it can. It can look really funny. And I've actually
Speaker 1: read stories of this being a real problem for people
Speaker 1: who have tried transporting kimchi in luggage and airplanes. I
Speaker 1: don't know if they let you do that anymore, but
Speaker 1: this at least has been a problem for some people.
Speaker 1: I'd read about it in the past, Like you would
Speaker 1: take a jar overseas with you or something, and sometimes
Speaker 1: the jar can explode in your luggage and soak everything
Speaker 1: in spicy, rotting cabbage water, which is delicious but not
Speaker 1: really something you want to fully saturate your underwear. Um
Speaker 1: that that that article from The Salt that I mentioned earlier.
Speaker 1: They have a little bit more about the about taking
Speaker 1: kimchi into space, and they actually talked to you, asked
Speaker 1: younaut about this, asking you know, what was it like.
Speaker 1: And the one thing they point out is that for
Speaker 1: the kimchie to go into space, it had to be
Speaker 1: radiated to kill all of the micro organisms in it,
Speaker 1: which he says left it looking quote so saggy. It
Speaker 1: looked like it was a hundred years old. So it apparently,
Speaker 1: you know, didn't taste maybe like terrestrial kimchi, but apparently
Speaker 1: it tasted. It tasted enough like kimchi that it did
Speaker 1: the job. You know. It um It packed the you know,
Speaker 1: the spicy fermented punch, and it reminded them of home.
Speaker 1: So Nitian accomplished. Well, this is an important point because Okay,
Speaker 1: so obviously there there are multiple reasons. You'd probably want
Speaker 1: to kill all of the microbes in the kimchi, and
Speaker 1: you'd want to radiate it before you take it into space.
Speaker 1: You definitely don't want kimchi blowing the lid off of
Speaker 1: its jar inside a space station. That would be uh,
Speaker 1: that could be disastrous, like spills are not good in microgravity.
Speaker 1: But anyway, it really emphasizes that that kimchi is at
Speaker 1: its core a living product, and you can have kimchi
Speaker 1: that's been sterilized. I mean sometimes people sometimes I cook
Speaker 1: it before I eat it, especially when it gets older.
Speaker 1: You know, you can saute in the pan and add
Speaker 1: as a as an ingredient to things. And then of course,
Speaker 1: like kimchi fried rice, fantastic delic just but at that
Speaker 1: point it is sterile before cooking it or before radiating it.
Speaker 1: If you've just got a jar of kim chie sitting
Speaker 1: in your fridge, I mean, this is a living organism. This,
Speaker 1: this kim chi that you're eating. The life goes on
Speaker 1: within it, and it will even though the fermentation will
Speaker 1: be much slowed down by the temperatures inside a refrigerator. Uh,
Speaker 1: it is still alive and things are still happening there.
Speaker 1: It is still maturing, it is still evolving as an ecosystem. Absolutely.
Speaker 1: Now speaking of that that ecosystem, let's bring everything back
Speaker 1: down from space. Uh, not only to the Earth, but
Speaker 1: under the earth. Because we've already referenced a few types
Speaker 1: of fermentation. Uh. That entails bearing a vessel or using
Speaker 1: some sort of a gutter, you know, made in earth
Speaker 1: or stone. It's worth noting that the traditional means of
Speaker 1: creating kim she also entails bearing, uh, the the container
Speaker 1: bearing what Michael Pollen in his two thousand book Cooked
Speaker 1: described as a child old sized earthenware croc. So I
Speaker 1: wanted to read just an excerpt from that that excellent book, which,
Speaker 1: by the way, mentions kimchi a lot. So if you
Speaker 1: if you're looking for, you know, a really good book
Speaker 1: about about food science and history, you know, a horse
Speaker 1: always turned to Michael Pollan, but particularly this book has
Speaker 1: a lot of kimchi in it. But here's what he
Speaker 1: had to say. Quote. Nowadays, pit fermentation strikes most of
Speaker 1: us as primitive, strange, and unsanitary. Yet we think nothing
Speaker 1: of aging cheese is underground in caves, which is not
Speaker 1: so very different? And how different is a pit fermentation
Speaker 1: really from fermenting food in a croc? Earthenware, as it's called,
Speaker 1: is really just earth once removed, cleaner and more portable, perhaps,
Speaker 1: but otherwise the same basic idea. Even today, Koreans bury
Speaker 1: their child sized crocs of kimchi in the backyard in
Speaker 1: order to maintain the even cool conditions that the lacto
Speaker 1: bacilly prefer. The earthenware croc is a good reminder that
Speaker 1: every ferment is food and drink stolen or borrowed from
Speaker 1: the earth by temporarily diverting its microbial gravitational pull to
Speaker 1: our own ends. Everyone knows who stole the power of
Speaker 1: fire from the gods for the benefit of humankind, but
Speaker 1: who is the prometheus of pickling. That sounds like a
Speaker 1: great story to where is I would be shocked if
Speaker 1: there was not some mythical tradition that had a story
Speaker 1: of a god giving the gift of pickling or fermentation
Speaker 1: to humans. Yeah, it's seen. I hadn't haven't had a
Speaker 1: chance to look into it, but I would assume that
Speaker 1: some god or another would have that at least on
Speaker 1: their their resume. You know. For Paullen's part, he goes
Speaker 1: on in this book to think, well, okay, pickling, fermentation,
Speaker 1: these are not going to be as as jazzy as
Speaker 1: killing animals or um or or certainly creating fire, these
Speaker 1: other acts of early human endeavor that were so important.
Speaker 1: But there's still there are others, including sand or cats
Speaker 1: we mentioned earlier. Who has a only put it on
Speaker 1: par with fire in our history, saying like, like pickling,
Speaker 1: um fermentation, Uh, these processes are up there with our
Speaker 1: fire technology in terms of their importance to our our
Speaker 1: our history. Well, yeah, I would say, especially if you
Speaker 1: go with you Remember we talked previously about the importance
Speaker 1: of bread in the development of human civilization because of
Speaker 1: the kinds of nutrition that it could provide relative to
Speaker 1: its own ingredients raw, and of course fermentation is an
Speaker 1: important part of many bread so there are also unleavened breads.
Speaker 1: But you know, yeah, so I think it's there at
Speaker 1: the heart. I don't know if it's quite at the
Speaker 1: level of fire, but especially if you're going for like
Speaker 1: the richness of human life and pleasure and foods and
Speaker 1: all that, it's got to be right up there. Now,
Speaker 1: I do want to say something real quick about the
Speaker 1: idea of the prometheus of pickling. Now, in this case,
Speaker 1: I think pollen is is using pickling a little bit informally.
Speaker 1: But there is a distinction to be made between pickling
Speaker 1: and fermentation. Basically, pickling is preserving food with a salt brine,
Speaker 1: while fermentation involves bacteria. So some pickled foods are also fermented,
Speaker 1: but they don't have to be. Yeah, Like, for example,
Speaker 1: you can make pickled foods that have no microbial action
Speaker 1: in them at all. Like you just dump a bunch
Speaker 1: of like vinegar and other flavors that you can make
Speaker 1: a pickle brine out of vinegar and salt and sugar
Speaker 1: or something like that, and it will be so vinegary
Speaker 1: that nothing will live within it. So there's no fermentation
Speaker 1: going on at all. Yeah, Like I do some of
Speaker 1: these box meals, um like you know, Martha Meles, etcetera.
Speaker 1: And uh, and they'll often have me do some like
Speaker 1: very quick fridge pickles, or sometimes they don't even go
Speaker 1: in the fridge. And I have to say, sometimes I
Speaker 1: feel like I doubt myself. I'm like, am I really
Speaker 1: making something that I can call it pickle? Or did
Speaker 1: I just throw some salt at some cucumbers for like
Speaker 1: ten minutes? Oh, you can call it a pickle. It's
Speaker 1: just not fermented. I mean, pickling is is a broader umbrella.
Speaker 1: Um and and there are major differences in flavor. I'm
Speaker 1: sure you've noticed. Like you can achieve the same preservative
Speaker 1: fact either by salting cabbage allowing the lactic acid bacteria
Speaker 1: to thrive, which in turn produces lactic acid, which lowers
Speaker 1: the pH of the environment and preserves the cabbage. Or
Speaker 1: you can just dump a bunch of acid like vinegar
Speaker 1: directly onto the food and just cut out the bacterial middleman.
Speaker 1: But you're losing a lot when you do that, because
Speaker 1: the bacterial middleman actually makes a huge difference in the aroma, taste,
Speaker 1: and texture of the final product that the bacterial middleman
Speaker 1: produces a much greater diversity of flavorful compounds. Vinegar pickled
Speaker 1: foods can be great. I like them sometimes, but they
Speaker 1: are fairly one note. Fermented foods, on the other hand,
Speaker 1: or very often described as funky and complex because of
Speaker 1: these wide ranges of of different flavorful compounds that come
Speaker 1: out of the microbial metabolism just one example, and there
Speaker 1: are tons of them. But for for example, the cabbage
Speaker 1: fermentation process in many kinds of kimchi produce is not
Speaker 1: only lactic acid, but compounds like diocetal, which in other
Speaker 1: contexts diocetel is known to produce a distinctly buttery taste. Sometimes,
Speaker 1: for example, it's used as a flavoring in popcorn quote
Speaker 1: butter um. But this is one of the reasons that
Speaker 1: fermented vegetables like kim chi can sometimes take on these
Speaker 1: counterintuitively dairy reminiscent flavors buttery, nous, cheesiness despite having no
Speaker 1: dairy content. Uh. And you might have encountered a similar
Speaker 1: flavor crossover from alcoholic beverages like wine, like if you
Speaker 1: ever had a a chardonnay that tasted strangely like butter Uh.
Speaker 1: There could be multiple reasons for that, but a major
Speaker 1: one is diocetle. Diocetal from the metabolic processes of lactic
Speaker 1: acid bacteria in the wine could be partly responsible for
Speaker 1: that buttery flavor. And anyway, it's it's all of these
Speaker 1: metabolic byproducts of the lactic acid bacteria that that create
Speaker 1: this richness and complexity of flavor that comes along with
Speaker 1: lacto fermented vegetables like kimchi. Okay, we need to take
Speaker 1: a quick break, but when we come back, I'm going
Speaker 1: to be chatting about vegetable fermentation with Dr Esther Miller.
Speaker 1: Thank thank We are back, and now we're going to
Speaker 1: head straight into my chat with Dr Esther Miller, who
Speaker 1: studies fermentation and microbial ecology at a center called the
Speaker 1: Wolf Lab at Tufts University. Here we go. Esther Miller,
Speaker 1: thanks so much for joining us today. So to start off,
Speaker 1: could you talk a bit about your background and how
Speaker 1: you got into studying microbial ecology. Sure. Yeah, So I
Speaker 1: did a sort of wandering path to get into a PhD.
Speaker 1: So I started doing research at Oxford University on inside
Speaker 1: and locust warming, and I moved to Sydney and looked
Speaker 1: at locust in Australia. And then I became a high
Speaker 1: school teacher but miss science, and then did walk in
Speaker 1: a biotech company that also looked at the insects. So
Speaker 1: I did a sort of diverse range of things before
Speaker 1: um coming to a PhD at Task University, and it tough.
Speaker 1: You do rotations, and I did a bit of a
Speaker 1: project in the Wolf lab and I loved it. And
Speaker 1: I love that it's uh ecology and so you're looking
Speaker 1: at how communities interact and how different populations interact is
Speaker 1: but it's very small. I can do it in the lab.
Speaker 1: I don't have to go across Australia gathering locust or
Speaker 1: anything like that. It's just on a blade in the lab.
Speaker 1: It's very simple. But it's also in food, and I
Speaker 1: really love food, and it was in cheese um and
Speaker 1: I love cheese, and you know, I moved to America
Speaker 1: from the UK and I didn't have access to good cheese.
Speaker 1: So the lab was a great place for getting cheese.
Speaker 1: But I wanted to keep on with the plant research
Speaker 1: and that sort of background, so I asked Professor Wolf.
Speaker 1: So I'm in the Wolf Club. I asked Professor Wolf
Speaker 1: if I could start looking at microbial ecology. So the
Speaker 1: same things in the same questions that he was asking,
Speaker 1: but in u sauer kraut and fermented vegetable products and
Speaker 1: he'll at me and it's um. It was great. So
Speaker 1: from there I started developing ecological questions in this fermented
Speaker 1: vegetable wild So one thing I can't leave off. You
Speaker 1: mentioned that you had done research with locusts. I was
Speaker 1: reading in another interview with you that I think was
Speaker 1: in Cook's Illustrated a few years ago, that you said
Speaker 1: that part of that research involved tickling the legs of locusts.
Speaker 1: But I was curious what what that was in service
Speaker 1: of studying What were you trying to find out by
Speaker 1: tickling locust legs? Yeah? So, um, the desert locus, the
Speaker 1: scog area, which all of your listeners will know if
Speaker 1: they've ever been to a pat shop and looked at
Speaker 1: the lizard food. So the yellow and black locusts that
Speaker 1: hop around and you feed them to your lizards, that's
Speaker 1: the desert locusts. And they come in that dusky like
Speaker 1: they're sort of dar when they're adults, but they also
Speaker 1: come in bright green and it's the exact same species.
Speaker 1: It's the same thing. It just has a phase change
Speaker 1: where it goes from a solitary, beautiful grasshopper that's all
Speaker 1: alone eating, not hiding anybody, and then there can be
Speaker 1: a shift um and it's a serotonin spite that shifts
Speaker 1: until it becomes gregarious and they start swarming. So the
Speaker 1: research there it was Professor Steve Simpson was looking at
Speaker 1: how what is that shift, what is triggering that serotonin spike,
Speaker 1: and he found if you like agitate them, if they're jostling,
Speaker 1: if you sort of have them in a crowd and
Speaker 1: they start knocking against each other, that's when that chemical
Speaker 1: shift happens. So it was simulating locust knocking against one another.
Speaker 1: So tickling them, yeah, yeah, you said, you use the
Speaker 1: paint brush to tickle their So you tickle a locust
Speaker 1: lag for five seconds every minute for eight hours, and
Speaker 1: then it will have a completely different behavior. So the
Speaker 1: the the parents takes a generation to come through and
Speaker 1: it will be brown and yellow later on. But the
Speaker 1: behaviors it goes from being uh, scared of locus and
Speaker 1: running away to wanting to aggregate, like moving together. Did
Speaker 1: you have any interest in fermentation as food before you
Speaker 1: got into the science of it particularly I like, I
Speaker 1: like food, and so I think that's what drew me
Speaker 1: to the lab, as well as the strong emphasis on outreach.
Speaker 1: So it's very hard to get people excited about bacteria
Speaker 1: and people are just like, oh, it's a disease, or
Speaker 1: what your hands, or of the use of antibiotics. But
Speaker 1: this is something that I can take a cheese or
Speaker 1: a jar of kimchi and talk to somebody about it,
Speaker 1: and I think, um, it became important to me to
Speaker 1: be able to talk to the general public about research.
Speaker 1: I think from a teaching background, finding a way that
Speaker 1: you can easily explain complex scientific ideas by being like, hey,
Speaker 1: this cheese is like this, and why is it like that?
Speaker 1: And what is going on with this microbe and that microbe?
Speaker 1: Oh that's great, Yeah, that's like the Sauer Kraut can
Speaker 1: be a foot in the door to a to a
Speaker 1: broader view of the microbiological world. Yeah, and the cheese
Speaker 1: as well, Like you can you can take cheese anywhere
Speaker 1: and people will be excited because it stinks like it
Speaker 1: immediately draws people in because you're like, hey, smell this,
Speaker 1: and then they're like, okay, that's really cool. Um boy,
Speaker 1: I suppose you can do that with kimchi as well.
Speaker 1: UM and sauer kraut. They have like smells and textures
Speaker 1: that are exciting, you know, totally. Um, So maybe you
Speaker 1: can start off by giving me sort of a character
Speaker 1: sketch of lactic acid bacteria as a group. What are
Speaker 1: these organisms like, what do we know about them? And
Speaker 1: how do you think about them? So lat gas of
Speaker 1: bacteria are a whole group, and there's many different you
Speaker 1: sees in this group. And then for the most part
Speaker 1: they are called grass generally regarded as safe. So the
Speaker 1: FDA doesn't really care about them. Um, there are in
Speaker 1: so many food products. The more you study, the more
Speaker 1: you find, so there's hundreds and you know, so they're
Speaker 1: not gonna go around saying this one is safe and
Speaker 1: this one and this one. They're just as a blanket,
Speaker 1: they're safe. Um, there are in so many foods. Um.
Speaker 1: And as a rule, they take sugars and they ferment
Speaker 1: them into electic acid. That's pretty much the basics. Some
Speaker 1: of them are a little more complex and they'll turn
Speaker 1: things into lactic acid and um acetic acid and CEO
Speaker 1: two and so those are the hetero fomentors. They do
Speaker 1: more than one thing, so they sort of think they're
Speaker 1: making two different assets, whereas the home of fomentors there
Speaker 1: is doing one thing. They're just making lactic acid. And
Speaker 1: that's the two big groups when you're thinking about lacto acid,
Speaker 1: and if I ever call them LBS, it's lactic acid veteria.
Speaker 1: So we know lactic acid bacteria are one of the
Speaker 1: major players in UH in vegetable fermentations like kim chi
Speaker 1: or sauer kraut. But could you give us a broader
Speaker 1: picture about what's going on in the whole life cycle
Speaker 1: of a of a microbial ecosystem inside a vegetable fermentation.
Speaker 1: So if you take like a jar of freshly made
Speaker 1: kim chi and it starts to ferment, who else is
Speaker 1: in this microbial cast of characters and what do the
Speaker 1: struggles for dominance look like inside that jar? So I'm
Speaker 1: sure you and your lessons have maybe started experimenting during
Speaker 1: COVID with fermentation, so you know that um if anyone
Speaker 1: started on sauerkraut, I think sauerkraut is under utilize compared
Speaker 1: to sour dough. But if you've done any fermenting of
Speaker 1: souer crout, which I think you shared um do you
Speaker 1: know that you don't add a starter so that's sour dough.
Speaker 1: When you first do the starter culture, you're just relying
Speaker 1: on the natural who is there to inoculate the ingredients.
Speaker 1: So you take cabbage or if you're making kimchi, other ingredients,
Speaker 1: or you can make other ferments like adding in carrots
Speaker 1: or whatever, and the bacteria, these light casa bacteria just
Speaker 1: present on the surface. But the one the first thing
Speaker 1: that I did in my project was paid out the cabbages,
Speaker 1: and I found that light casa bacteria really low. If
Speaker 1: you're looking at the bacteria present on a vegetable, there
Speaker 1: are lots and lots of proteo bacteria, many many things
Speaker 1: like pseudomonas um, spingle mona. So these are bacteria that
Speaker 1: like living on plant leaves, and for the most part,
Speaker 1: they're really beautiful and colorful because they contain pigments that
Speaker 1: protect the bacteria from UV light. So if you think
Speaker 1: of a cabbage out in a field, it's actually exploited.
Speaker 1: It really really high levels of UV light and it
Speaker 1: doesn't have a lot of water accessible on the leaf surface.
Speaker 1: So leaves are normally covered in a waxy film and
Speaker 1: so there's not a lot of nutrients, there's had a
Speaker 1: lot of water. It's really hard to survive. And the
Speaker 1: bacteria that are there have a lot of pigments and
Speaker 1: ways that they can adhere to the surface of the
Speaker 1: plant and help them survive. And it's not really the
Speaker 1: lactic astive bacteria's way of living, so not really high
Speaker 1: like very abundant on the leaf. But when you chop
Speaker 1: that leaf up to make your SA crowd, you're releasing
Speaker 1: those punch sugars. You're making them like very readily available.
Speaker 1: And then when you add the salt, you further draw
Speaker 1: out those sugars and you completely change the playing field.
Speaker 1: So you've gone from a high oxygen, highlight, low nutrient
Speaker 1: condition to all the nutrients in the leaves are out
Speaker 1: and slashing about. You take away the oxygen when you
Speaker 1: push it down into a messenger, and you add salt,
Speaker 1: and this is really really strong abiotics selective pressure that
Speaker 1: will change who can live. And that's when the lactics
Speaker 1: of bacteria really come into their own and they can
Speaker 1: start increasing in abundance. Now I mentioned earlier the two
Speaker 1: big groups of lactic aso bacteria, the petro fermentors and
Speaker 1: the homo fermentors. So at the very start of fermentation,
Speaker 1: we get a massive increase in the hetero fermentors, so
Speaker 1: as things like luconna stocks and versalia um and they
Speaker 1: really take off and they're super abundant, and they're making
Speaker 1: lactic acid and acetic acid. Now these two acids start
Speaker 1: lowering the pH and that makes it easier for the
Speaker 1: homo fomentous to start growing. So you sort of see
Speaker 1: a two phase I wish I had a white water
Speaker 1: you could draw it out where you have one population
Speaker 1: that increases and then a second population, so a second
Speaker 1: wave UM, and that lowers the pH even more. And
Speaker 1: as the pH falls um there was proteo bacteria that
Speaker 1: we're talking about. They can't survive and they won't they
Speaker 1: won't be present at the end of amentation. So if
Speaker 1: I'm corrected, this first group the hetero from enters that
Speaker 1: produced the multiple byproducts you said lactic acid and acetic acid.
Speaker 1: So acetic acid would be basically the the acid and vinegar, right,
Speaker 1: and lactic acid is also what's coming out of the
Speaker 1: homo from enters, the lactic acid bacteria that come in
Speaker 1: the second wave UM, and is that am I correct
Speaker 1: in thinking that's also the same thing that builds up
Speaker 1: in our muscles when we exercise and start to feel
Speaker 1: the aching and and all that sort of the presence
Speaker 1: of the lactic acid bacteria causes the pain of exercise. Well,
Speaker 1: it's the same lactic acid. I'm sorry, did I say bacteria. Sorry,
Speaker 1: I didn't mean to say that the lactic acid. Yes, yeah, yeah, exactly, yes.
Speaker 1: And actually lactic acid is a less harsh acid. So
Speaker 1: if it was just fomented by hetero fomentos and it
Speaker 1: just we ate a sour crout that was just made
Speaker 1: with a stic acid, it wouldn't be that nice. It
Speaker 1: would be very very would be like a very harsh
Speaker 1: like a pickle. Like you wouldn't eat all of the
Speaker 1: pickle juice because it's very vinegary um. But when you
Speaker 1: have sour krout, it should have a softer, buttery flavor.
Speaker 1: So you have to sort of trust me on this
Speaker 1: one and go home and eat some and compare it
Speaker 1: to you just straight pickles, which are quite acidic, Because
Speaker 1: that lactic acid has a softer um like, it's not
Speaker 1: as sharp. Yeah, that's definitely something you notice, is a
Speaker 1: difference between quick pickled foods that you use vinegar to pickle,
Speaker 1: versus fermented foods where it comes from the bacteria. It's
Speaker 1: a much more soft, round, complex kind of flavor. So
Speaker 1: so normally when you ferment vegetables and UH and you're
Speaker 1: trying to you know, you salt them, you make a brine,
Speaker 1: and you encourage the lactic acid bacteria. You said, you
Speaker 1: see these two broad spikes with the hetero fomenters and
Speaker 1: then the homo fomenters UM. But even within that, you're
Speaker 1: still going to see a lot of different species involved,
Speaker 1: right that there can be widely different profiles of what
Speaker 1: exact lactic acid bacteria are taking over. Is that correct? Yes,
Speaker 1: there's a lot so UM looking at who's there, there's
Speaker 1: just some big players, so they'll be like lact to
Speaker 1: basilist broad vis in basically everything at a really high percentage,
Speaker 1: and then there'll be a lot of UM low numbers
Speaker 1: of many other ones. So we've just recently done a
Speaker 1: survey of North American fermented vegetable products UM, which I
Speaker 1: was really excited about because there's a lot of research
Speaker 1: on UM Asian products. So there's a whole research institute
Speaker 1: of kimchi in Korea, and there's um a lot of
Speaker 1: research in Europe, but this is the first United States
Speaker 1: sauner Craft survey and we found on average teen point
Speaker 1: eight species of lactic gas of bacteria her jar, but
Speaker 1: most of them are as some of the really common
Speaker 1: lactic gas of bacteria. They take, They take up the bulk.
Speaker 1: So would you find any noticeable differences in in like
Speaker 1: aromas or flavors produced depending on what the microbial ecosystem
Speaker 1: in the fermented jar vegetables looks like. I haven't. I
Speaker 1: haven't done any specific research on that, but I haven't
Speaker 1: myself noticed anything. I think there can be a big
Speaker 1: difference between kimchi and sauerkraw, which is hard to measure
Speaker 1: in terms of the bacteria that are present because there's
Speaker 1: so many other flavors going on. So some kim cheese
Speaker 1: are fermented at a lower temperature, and when you're fermenting
Speaker 1: in a really cool temperature, like between ten to fourteen
Speaker 1: degrees celsius, you're promoting those hetero fermentors, so you get
Speaker 1: a different flavor. So there can be a lot of
Speaker 1: asalia in kimchi, which is less prevalent in souer crawl
Speaker 1: like they'll still be there but in lower numbers. But
Speaker 1: it's very hard to compare the flavors and attribute that
Speaker 1: to the bacteria when you've also garlic, ginger, red paper,
Speaker 1: and everything else. That's one thing I found hard in
Speaker 1: doing this survey is that every producer might have different vector,
Speaker 1: but they all have like the slight tweaking of recipes.
Speaker 1: So some had like caraway seeds or they threw in
Speaker 1: an apple just like So you mentioned that that the
Speaker 1: lactic acid bacteria tend to be found in very low
Speaker 1: numbers if you just takes a raw leaf of cabbage
Speaker 1: from the farm before fermentation. So where do we have
Speaker 1: any idea about where these microbes generally come from. Is
Speaker 1: it just something that's probably there on a leaf of cabbage,
Speaker 1: even though it's in very small numbers, and then the
Speaker 1: fermentation environment helps those numbers bulk up over time or
Speaker 1: there are other possible vectors. Yeah, So I went out
Speaker 1: to farms or common gardens um in the summer of
Speaker 1: twenty seven and team and tried to find environmental sources
Speaker 1: of lactics of bacteria. So I took soil and leave
Speaker 1: samples and not cabbage leaf um. We'd leaves are things
Speaker 1: that were just growing next to crop plants um, and
Speaker 1: I found that they had pretty low levels of lacticas bacteria.
Speaker 1: So I didn't find like a big environmental reservoir of
Speaker 1: these bacteria, which I think it's pretty incredible that we
Speaker 1: know so much about them in the human micro like
Speaker 1: the human got microbiome and probiotics and probiotics and fermented foods,
Speaker 1: but very little is known about the ecology, and I
Speaker 1: couldn't find too much. I think I definitely talked about
Speaker 1: it in the in a previous podcast about maybe they're
Speaker 1: being affected in by insects if you are US papers
Speaker 1: where honey bees have lacticas bacteria and that gut um,
Speaker 1: and they're very specific two bees. Though, I think because
Speaker 1: bees taken nectar and then the sugars in the nect
Speaker 1: you can get broken down by l to gas a bacteria.
Speaker 1: But I haven't yet found any evidence that the insects
Speaker 1: and the insect droppings go on to be the source
Speaker 1: of black to Gasa bacteria and fermented vegetables. So perhaps
Speaker 1: a very small amount of black to Gasa bacteria in
Speaker 1: soil can then try and like dispussed onto cabbages repeatedly
Speaker 1: and then maybe it's just low levels everywhere it's it's
Speaker 1: still a puzzle. Is it possible also that some amount
Speaker 1: of it just comes from the kitchen environments or other
Speaker 1: environments where this where fermentations are prepared, that it's on jars,
Speaker 1: it's on spoons and all that kind of stuff that's
Speaker 1: been sort of talked about a lot. And I'll have
Speaker 1: to look up the name for you, but there was
Speaker 1: a recent paper where they looked at stuttle Craft facility,
Speaker 1: so they I think there was at one facility in
Speaker 1: Rhode Island. They went to this one place and they
Speaker 1: sampled fridges, doors, walls, everything, and they didn't find like
Speaker 1: Casa bacteria in the environment. They only found levels on
Speaker 1: the cabbage. But if you're thinking about making sour crowd
Speaker 1: in a facility, you're going to have tons of cabbage.
Speaker 1: So even if you put together like ten cabbages in
Speaker 1: one giant fact, there's a lot of cabbage and you
Speaker 1: only need a tiny bit of the bacteria to make
Speaker 1: it to get it to take off. Whereas if you
Speaker 1: think if you were making it at home and use
Speaker 1: half a cabbage, then just by probability, by chance, you
Speaker 1: might make one that didn't have enough or didn't have any.
Speaker 1: But if you multiply the amount of ingredients, I think
Speaker 1: you will always have some amount. I would like to
Speaker 1: guess bacteria. Now, was I reading that previously you did
Speaker 1: some research with trying to grow sterile cabbage in order
Speaker 1: to to inoculate it with bacteria and see how the
Speaker 1: bacteria did on it. Yeah, I'm very excited about it.
Speaker 1: It came out in the Journal of Visualized Experiments, and
Speaker 1: then I couldn't film because of COVID, but they will
Speaker 1: be coming in on Wednesday. UM. But I managed to
Speaker 1: grow cabbages and I can send you pictures. UM. I
Speaker 1: managed to grow cabbages in glass tubes and they are
Speaker 1: sterile as far as I can tell. Like you know,
Speaker 1: maybe there's some media that one bacteria could grow on,
Speaker 1: but as far as we can tell, they're completely sterile,
Speaker 1: and they're happy, and they're growing in calcaine clay. You
Speaker 1: can articulate that. So if you put in the articlave
Speaker 1: high heat, high pressure, will be sterile at some nutrient
Speaker 1: broth and they're really happy. And now did that research
Speaker 1: involve you trying to see what kind of environment those
Speaker 1: previously sterile cabbages would make for different microbes or was
Speaker 1: that just to study the cabbage itself and how it
Speaker 1: could how well it did without a microbiome. No, I
Speaker 1: wanted to do actual competition experiments with large cast of
Speaker 1: bacteria and the philosphere microbiome. So the philosphere is the
Speaker 1: community of bacteria living on a leaf. So I wanted
Speaker 1: to say, well, maybe like to cast a bacteria in
Speaker 1: low abundance because they need eat a particular microbe to
Speaker 1: grow with or there's competition. So I made all of
Speaker 1: this sterile cabbage. It took me years and then I
Speaker 1: inoculated it. We lead Casa bacteria and they don't grow.
Speaker 1: Like if you just spray a cabbage with lat to
Speaker 1: caste bacteria and it's happy. You don't put any other
Speaker 1: thing in there to compete with it. It won't grow
Speaker 1: the cabbage or the lactic acid bacteria. The cabbage is fine.
Speaker 1: The cabbage. I wasn't interested. I haven't done any measuring
Speaker 1: of cabbages or their growth. Um they do find with
Speaker 1: or without a microbiome. I sprayed some yeast on cabbages
Speaker 1: once and they didn't enjoy that. The cabbages brown and
Speaker 1: just with it. But bacteria fine on cabbage, they don't
Speaker 1: influence the cabbage. But yeah, I did twenty bacteria that
Speaker 1: you just naturally find on a cabbage, and things like
Speaker 1: the pseudomonist that I mentioned. So things like that break
Speaker 1: them on the cabbage and they will increase and you
Speaker 1: will see like they're happy growing on a cabbage. The
Speaker 1: lattic as a batteria tank. So it's very hard to
Speaker 1: do an experiment with something that won't grow. Like I
Speaker 1: mix it with other things, they grow bacteria gust Wow.
Speaker 1: So we know that obviously these lactic acid bacteria are
Speaker 1: the main player and vegetable fermentations, but there are fungal
Speaker 1: microbes like yeast, so we've mentioned a little bit that
Speaker 1: are major players, and other kinds of fermentation of course,
Speaker 1: in like bread or in wine or beer. Did you
Speaker 1: mention over our email that um that in looking at
Speaker 1: store bought preparations of kimchi, you've found yeast in some
Speaker 1: of them. That seems kind of surprising. Yeah, So I
Speaker 1: tried really hard to find some literature on this, and
Speaker 1: you only see a few papers from a long time
Speaker 1: ago stating at yeast um sometimes found as spoiler organisms.
Speaker 1: But when I did this North American sourkrout survey or
Speaker 1: fermented vegetable product survey, so it was sour karts and
Speaker 1: kin cheese. I found over half of them had yeast,
Speaker 1: like a lot, a lot of yeast, Like some of
Speaker 1: them had more counts of yeast than bacteria, which I
Speaker 1: was really surprised by. So the FA the use that
Speaker 1: I found is safe. There are things like kazakhstania, which
Speaker 1: you do find in sour dough, so they're not they're
Speaker 1: not toxic, but everything that you read says the undesirable
Speaker 1: and fermented vegetable products because they give musty, yeasty, sort
Speaker 1: of dankish flavors I guess, and they can form a film,
Speaker 1: which I think is pretty off putting if you're trying
Speaker 1: to create a new product and that's covered in a
Speaker 1: yeast film. Yeah, you want your sour smell like skunky beer. No,
Speaker 1: definitely not, it's already Yeah, so tough. So I when
Speaker 1: I had this, I had fifty one jars and I
Speaker 1: was delighted, and I was like, Hey, who wants some?
Speaker 1: And I would. I opened and sampled them all in
Speaker 1: the conference room, a smaller room than the toughs, and
Speaker 1: people were not happy. They're like, Wow, the whole room
Speaker 1: stank for a week. I think it's just in an
Speaker 1: enclosed space. Opening fifty jars of sauer kraut and kim
Speaker 1: schi was a little much, but yeah, and I tried
Speaker 1: to eat them all, but I I really couldn't. That's
Speaker 1: a lot. But you couldn't eat fifty jars of kimchi
Speaker 1: by yourself or sauerkraut and kimchi. No. I tried so
Speaker 1: hot and I can do it. And part that's why
Speaker 1: I wrote the grant, as like, now I can get
Speaker 1: to eat all of it. If I write a grant
Speaker 1: that says I need to buy them all so well,
Speaker 1: that makes me think you you correctly guessed that. One
Speaker 1: of the things that got me interested in talking about
Speaker 1: kimch on our podcast is that I had been trying
Speaker 1: to make it at home for the first time recently.
Speaker 1: Uh And one thing that has so I've loved kimchi
Speaker 1: for years, and I've always put off trying to make
Speaker 1: it because it seemed like a scary, daunting, potentially dangerous
Speaker 1: procedure if you're fermenting things and you don't know what
Speaker 1: you're doing. But honestly, I've I've found it easier than
Speaker 1: I expected it to be, So I guess one thing
Speaker 1: a lot of people are probably wondering is how safe
Speaker 1: is it to experiment with making sauerkraud or kimchi or
Speaker 1: some other lacto fermented vegetable. Is this something that's probably
Speaker 1: gonna poison you if you screw it up, or is
Speaker 1: it pretty forgiving. That's that's a great, great question, because
Speaker 1: I think people are really scared, and when people come over,
Speaker 1: they're like, because I have a lot of ferments on
Speaker 1: my friends these days, but they're actually pretty safe. Anything
Speaker 1: that's anaerobic, um, you're really really making it very hard
Speaker 1: for things like equally and mysteria to grow. So they're
Speaker 1: pretty safe if you do get the anaerobic conditions correctly.
Speaker 1: So sometimes if you're fermenting in a massenger and you
Speaker 1: have like a pocket of air on the top, you'll
Speaker 1: notice the very top layer of your ferment might be
Speaker 1: a little off, and then you can just take that
Speaker 1: off and then push it down so it's submerged. But
Speaker 1: probably not an official thing to say, so basically, as
Speaker 1: long as you've got the salt there and the stuff's underwater,
Speaker 1: it's it's going to be safe. Yeah. I think that's
Speaker 1: one thing that I found remarkable with everything that I've done,
Speaker 1: with everything that I've read. I think that's why I
Speaker 1: just love this project so much, because it seems so haphazard,
Speaker 1: like you're just taking random ingredients and salt, and yet
Speaker 1: it works so consistently um worldwide. You know, That's what
Speaker 1: blows my mind. The things that we found in this
Speaker 1: North American survey are the exact same things that they
Speaker 1: find in Europe to the exact same things that they
Speaker 1: find in everything in Asia. So you're like, it's so robust. Broadly,
Speaker 1: what do you find amazing about fermentation? Well, that bacteria
Speaker 1: that we don't know how they where they live in
Speaker 1: the environment. We can't find them in the environment get
Speaker 1: into everything that we eat, and a consistent like it's
Speaker 1: amazing we can't try them, but all over the world
Speaker 1: there's it's the same species and you can't follow it
Speaker 1: from a field to a cabbage. You know, that's amazing.
Speaker 1: That is amazing. Uh, I don't know. It's one of
Speaker 1: the things we actually love to talk about on this
Speaker 1: show is kind of the hidden realities, the things that
Speaker 1: are so important to human culture, but that you know,
Speaker 1: you wouldn't be able to see them looking at I
Speaker 1: mean you, I guess you don't see any microbes with
Speaker 1: your eyes normally unless they're starting a really big colony.
Speaker 1: But but even with scientific instruments, like you don't know
Speaker 1: where all these microbes are coming from. Yeah, it's it's amazing.
Speaker 1: Like I was trying to write a review on dispersal,
Speaker 1: like how do how does a bacteria get from here
Speaker 1: to that? And you can read about the moving miles
Speaker 1: and thousands of miles on wind. It just gets in
Speaker 1: the wind and just dispersed. But you you've got no
Speaker 1: way of really knowing unless you sort of make genetically
Speaker 1: modified bacteria and release them, which I'm not going to you,
Speaker 1: but you know, like, how could you know if there's
Speaker 1: bacterias that because they're so small, you'd never tracked them.
Speaker 1: I think it's amazing. So is there anything else you've
Speaker 1: been working on recently that you wanted to talk about? Well,
Speaker 1: I I was gonna say, and I forgot to mention
Speaker 1: that I am doing community assembly experiment. So I've got
Speaker 1: three yeast and three bacteria that were isolated. Most of
Speaker 1: them were isolated from that Sauerkroud survey. So I took
Speaker 1: the bacteria that I found in that survey, and I'm
Speaker 1: competing the yeast and the bacteria together in little jaws
Speaker 1: of sterile vegetable extract too, and I put them under
Speaker 1: different conditions, like different temperatures, different salt concentrations, um and
Speaker 1: using different cabbage extracts of red cabbage, grain cabbage, and
Speaker 1: Napa cabbage to see if any of those influence the
Speaker 1: presence of yeast. And actually, I think it looks like
Speaker 1: the temperature that I fermented at could be influencing the
Speaker 1: abundance of yeast. So at higher temperatures, perhaps you get
Speaker 1: more used. So maybe the North American fermenters are using
Speaker 1: different conditions and that's why the ferments have more used.
Speaker 1: But I'm still working in it. Interesting. So, if if
Speaker 1: you're making kimchi at home or making sarokraut at home,
Speaker 1: and you want to keep the yeast out, a lower
Speaker 1: temperature fermentation might be a better way to do that. Yeah,
Speaker 1: So if the temperature in your room is getting sort
Speaker 1: of like above twenty four degrees, you might want to
Speaker 1: put it in the basement or somewhere a little cooler.
Speaker 1: And I did notice that if you don't put salt in,
Speaker 1: it can go horribly wrong. The pH just doesn't fall
Speaker 1: as much because I tried that, and I was even
Speaker 1: adding like to cast of bacteria, and the pH wasn't
Speaker 1: dropping as well as it should with two. But there
Speaker 1: wasn't a big difference between two and four. So I
Speaker 1: think sticking at two percent salt is good. Am I
Speaker 1: understanding the causality right there that the salt essentially makes
Speaker 1: um makes an environment that's less hospitable for other types
Speaker 1: of bacteria and microbes to thrive. But the to gas
Speaker 1: in bacteria or tolerant of salt is that it is it.
Speaker 1: That's what I always assumed um and think is right
Speaker 1: when you have just regular cabbage. But I was using
Speaker 1: sterile felted vegetable extractures, you know, so just completely sterile
Speaker 1: media and adding lac to gas of bacteria in the east,
Speaker 1: so they allowed to gas about. You didn't have that
Speaker 1: much competition, you know, they're there with the East, and
Speaker 1: yet they still didn't do that well when there's no salt.
Speaker 1: Mm hmm. So maybe the salt is even helping it
Speaker 1: in some way. I think there's going to be something
Speaker 1: going on with the salt as well. M M, well
Speaker 1: that's very interesting. Yeah, all right, well, I think we
Speaker 1: have to call it there. But thank you so much
Speaker 1: for joining us today. This has been so great and
Speaker 1: we really appreciate you sharing your time and your expertise.
Speaker 1: It's been a lot of fun. Yeah, thank you very
Speaker 1: much for having me. Well, I guess that wraps up
Speaker 1: this episode, but once again, huge appreciation to Dr Esther
Speaker 1: Miller for taking the time to speak with us. And
Speaker 1: I will say, though this episode is over, there is
Speaker 1: that whole hidden world flowing into the fermentation jar, so
Speaker 1: it's possible that we may have to come back and
Speaker 1: explore other corners of that world again in the future.
Speaker 1: In the meantime, if you would like to listen to
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Speaker 1: to our excellent audio producer Seth Nicholas Johnson. If you
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