Speaker 1: Welcome to Stuff to Blow Your Mind production of My
Speaker 1: Heart Radio. Hey you welcome to Stuff to Blow Your Mind.
Speaker 1: My name is Robert Lamb and I'm Joe McCormick, and
Speaker 1: it's fermentation day here at the Stuff to Blow Your
Speaker 1: Mind podcast. We're gonna be talking about kim she one
Speaker 1: of my favorite foods of all time. Uh. And also
Speaker 1: later in the episode, just wanted to give you a
Speaker 1: heads up. Robert and I are going to chat about
Speaker 1: kimchi for a while first, but later on we're gonna
Speaker 1: be speaking with a bona fide fermentation expert from a
Speaker 1: Tufts fermentation lab. Her name is Dr Esther Miller, and
Speaker 1: it sounds like she's got one of the coolest jobs
Speaker 1: in the world. Yeah. Given the title we went with
Speaker 1: here kim che a song of salt and Cabbage, I
Speaker 1: guess it's a missed opportunity for us to have done
Speaker 1: some sort of um Wester Ross themed cold open skit
Speaker 1: about about kim she Well, I guess the real prince
Speaker 1: was promised in the story is the lacto Bacillus bacteria
Speaker 1: and and he must come in order to rescue the fermentation,
Speaker 1: for the jar is dark and full of spores. That's
Speaker 1: pretty good. But of course you know there's some there.
Speaker 1: There has to have been some pickling and from and
Speaker 1: or fermentation in the west Ro's books, because it seems
Speaker 1: like they were always lengthy descriptions of what kind of
Speaker 1: foods uh of characters were eating. Yeah, but a lot
Speaker 1: of it is I think like a classic Anglo cuisine inspired,
Speaker 1: which is is actually very low. Well, I don't want
Speaker 1: to be insulting, I would say at least the perception
Speaker 1: is that it's relatively low on on spices and and
Speaker 1: complex flavors. It tends to be a rather bland cuisine,
Speaker 1: kind of focused on grain, meat and dairy. All right,
Speaker 1: But then I do we do have to to point
Speaker 1: out that, I guess there was beer, there was cheese,
Speaker 1: there was bread. And that's one of the reasons that
Speaker 1: fermented foods are so fascinating because there there are these
Speaker 1: things that we often forget are fermented, like cheese and
Speaker 1: bread and chocolate, and then we have these fermented um,
Speaker 1: you know, staples of various fermented goods that you're going
Speaker 1: to have in your your kitchen. And also some of
Speaker 1: the more um elaborate examples. For instance, Uh, there's the kivak,
Speaker 1: which is a traditional Inuit food from Greenland in which
Speaker 1: little ox These these little birds are caught and then
Speaker 1: fermented in a seal skin that's buried beneath rocks. There's
Speaker 1: a great feature on this in the documentary series Human
Speaker 1: Planet that came out several years back and was at
Speaker 1: the time narrated by John Hurt. I gotta admit, as
Speaker 1: much as I love fermented foods, I have never tried
Speaker 1: that one, and a lot of the fermented foods that
Speaker 1: I've never really gotten into, or the various kinds of
Speaker 1: fermented meats and dairy products from around the world, which
Speaker 1: are extremely common. Though I think fermented vegetable dishes such
Speaker 1: as kim she have seen more of an international renaissance
Speaker 1: and in recent years. Yeah, I feel like when I
Speaker 1: was a kid, I wasn't as exposed to as many
Speaker 1: fermented food aside from these obviously fermented foods, you know,
Speaker 1: like they I remember being you supposed to sour kraud
Speaker 1: but not really digging it for a long time. But
Speaker 1: but now, well, you know, is that is that a
Speaker 1: good or a 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 was some
Speaker 1: sort of German um oh, some sort of purple cabbage
Speaker 1: type thing that I also didn't have a real strong
Speaker 1: uh attraction to at the time. But all these things
Speaker 1: have grown on me today. I love sauer kroud, and
Speaker 1: I love kim she. I love exploring the various fermented
Speaker 1: veggie or mushroom items you'll find uh in various cuisines.
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 to struggle. But ultimately, I don't
Speaker 1: know how much of this is his nature versus nurture
Speaker 1: with him though, Yeah, I wonder about that too, because
Speaker 1: for minute vegetables, definitely they can have strong kind of
Speaker 1: 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 wonder if
Speaker 1: there could actually be an instinct, or at least a
Speaker 1: slight predisposition that humans would have to find certain kinds
Speaker 1: of smells and flavors associated with vegetable fermentation appetizing, since
Speaker 1: this could be a possible vector to get useful gut
Speaker 1: bacteria and other beneficial microbes that I think there's good
Speaker 1: evidence that a lot of these good microbes do actually
Speaker 1: survive the digestion process and and can help recolonize the
Speaker 1: gut with with beneficial bacteria. And then of course having
Speaker 1: 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 kim chi or yogurt with
Speaker 1: the smell of food that's rotting due to an unambiguously
Speaker 1: unfriendly micro But in these cases, our visceral reaction to
Speaker 1: the smell, I think it's much different. It's sort of automatic,
Speaker 1: instinctive revulsion. Uh. You know, some people might be grossed
Speaker 1: out by the smell of kim chi or sauer kraut.
Speaker 1: But I think that negative reaction is qualitatively different than
Speaker 1: the like, you know, hot garbage kind of reaction people
Speaker 1: have to the smell of like real dangerous spoilage in foods. Yeah,
Speaker 1: like the like the actual like dead animal smell which
Speaker 1: really connects with us on a on a primal level,
Speaker 1: Like when you smell it, you it. You not might
Speaker 1: not be able to summon that smell in your head
Speaker 1: right now, but it's undeniable when you encounter it. Um
Speaker 1: And now I've I've I've read some different things about about,
Speaker 1: you know, kids and flavor, just through I think virtue
Speaker 1: of of being a parent. I know, there's the the
Speaker 1: argument that you know, since a child has a smaller
Speaker 1: body and is more susceptible to the dangers of of poisons,
Speaker 1: that that they are going to be overly sensitive to
Speaker 1: certain strong smells or flavors. UM. And there's also this angle.
Speaker 1: I've not done any like full research into it, and
Speaker 1: perhaps this would be a topic for the future, but
Speaker 1: I know that biopsychologist Julie Manila has researched the topic
Speaker 1: a bit regarding uh, you know, uh, whether we're born
Speaker 1: with certain food preferences in mind. And she has some
Speaker 1: work that shows that food preferences may be developed in
Speaker 1: the womb or during very early life. So we're talking
Speaker 1: prenatally and postnatally, involving both the amniotic fluid and rest milk.
Speaker 1: So if I'm understanding it correctly, the diet of a
Speaker 1: child's biological mother can influence the child's taste later on. Yeah,
Speaker 1: that would not be surprising to me. I mean, I
Speaker 1: think a lot of things from the from the parents
Speaker 1: environment can come through to the child like that. Um.
Speaker 1: But another thing, you know, I'm thinking about with with
Speaker 1: people's taste for fermented foods is that it could be
Speaker 1: a psychological framing issue. You know, We've talked before about
Speaker 1: the research showing that people you can take the same
Speaker 1: smell and that people might find it appealing if you
Speaker 1: blindfold them and tell them the smell is coming from
Speaker 1: a cheese, but find it disgusting if you blindfold them
Speaker 1: and tell them it's coming from a sock. Uh. For
Speaker 1: people on a Western diet who are unfamiliar with kim
Speaker 1: chie or with other fermented vegetables and find the smell
Speaker 1: off putting, it's possible that it's you know, that it's
Speaker 1: similar aromas that they would find appealing if they just
Speaker 1: had more of a reason to associate them with, say
Speaker 1: the idea of vegetables, because like some of the aromas
Speaker 1: that come off of kim chi can smell kind of cheesy,
Speaker 1: and that's a strange thing to smell coming off of
Speaker 1: vegetables if you're not used to it. Yeah, I've I
Speaker 1: think I've voiced a similar thing with Durian fruit before.
Speaker 1: Durian fruit, of course, is is beloved in many parts
Speaker 1: of the world, but sometimes is less appreciated, certainly in
Speaker 1: Western circles, and I think part of that is, like
Speaker 1: if my my take anyway, is that if you approach
Speaker 1: the Durian as being a cheese and not a fruit,
Speaker 1: then then that's going to dismantle some of these associations
Speaker 1: you you make, because when you take in the aroma
Speaker 1: of the Durian fruit. You might think, well, that that
Speaker 1: doesn't smell like I expect a fruit to smell. I'm
Speaker 1: more accustomed to a really sweet smell with a fruit
Speaker 1: or something much milder. But if you approach it thinking cheese,
Speaker 1: then I think you're in a better position to enjoy it. Yeah.
Speaker 1: I think that's a really good point, and it almost
Speaker 1: makes me wonder if there is there a certain kind
Speaker 1: of meditation practice that has been honed in order to
Speaker 1: ready the mind to exp orient's new flavors and aromas
Speaker 1: as pleasurable when you're not used to them. I wonder
Speaker 1: 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 consumption. 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 as a cheese and not
Speaker 1: a fruit thing that maybe entirely based as well. In
Speaker 1: my situation as kind of a Durian outsider, yeah, I
Speaker 1: can see that. But obviously, I mean, tastes that were
Speaker 1: once unfamiliar to us can become very very central to
Speaker 1: our way of experiencing food in the world. I mean,
Speaker 1: so I grew up loving pickled vegetables, but I did
Speaker 1: not um, I did not grow up with kim chi,
Speaker 1: and now kimchi is one of my favorite foods. I mean,
Speaker 1: if you 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 bonsch on, you know, all
Speaker 1: those little dishes like Korean side dishes of various different
Speaker 1: vegetable preparations and kimchi and things like that. That's the
Speaker 1: bulls eye for me. That's like the best thing, and
Speaker 1: it wasn't always there. So like clearly, our orientations about
Speaker 1: food can change as we mature or maybe I shouldn't
Speaker 1: say mature, just as we go on in life. So
Speaker 1: in terms of just fermentation in general. We'll get back
Speaker 1: more specifically to kim chi 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 our crowd 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: gonna find products of fermentation. And again this includes more
Speaker 1: obvious examples such as you know, the sour crowd and
Speaker 1: the kimchi, but it also means bread, cheese, salad, dressing, 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 sauerkraud and
Speaker 1: kimchi really have in common? What? What? What is it?
Speaker 1: What 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. It's 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 vegetable and products
Speaker 1: through the winter. Uh. The traditional preparation cycle for kimchi
Speaker 1: involves packing it into pots in the autumn that can
Speaker 1: be eaten throughout the winter, I guess throughout the rest
Speaker 1: of the year, when fresh vegetables would be hard to
Speaker 1: come by. So, as is often the case with food traditions,
Speaker 1: I think many forms of fermentation, vegetable fermentation likely followed
Speaker 1: a path of beginning with a mistake and then moving
Speaker 1: to utilitarian innovation as a preservative, but eventually just becoming
Speaker 1: a taste preference, becoming something people liked because it's good.
Speaker 1: But I also wanted to go back to a note
Speaker 1: you had on the idea of effervescence in fermentation. This,
Speaker 1: this idea of effervescence or bubbling uh this is actually
Speaker 1: one of my favorite things about certain kinds of kim chi.
Speaker 1: It's not always like this, but certain kinds of kim
Speaker 1: chi not only have these great complex flavors and pleasing crunch,
Speaker 1: it sometimes has something you don't find in other solid foods,
Speaker 1: which is a palpable taste of carbonation in the mouth.
Speaker 1: Sometimes kim che can kind of bubble and fizz and
Speaker 1: zing in your mouth while you're chewing on it, the
Speaker 1: same way that a sip of a carbonated drink does.
Speaker 1: And and this is one thing I really love that
Speaker 1: this bubbling property of fermentation is also 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 and bread as they metabolize the sugar in
Speaker 1: the dough. The effervescent property in uh in kim che,
Speaker 1: of course, is the is the ceo to produced by
Speaker 1: the bacteria as they break down the sugars in the cabbage.
Speaker 1: But this effervescent property of giving off bubbles or gas
Speaker 1: was actually probably where the word fermentation comes from. It's
Speaker 1: derived ultimately from the Latin word for very, meaning to
Speaker 1: boil or to seethe, and ancient Latin speakers probably would
Speaker 1: have been able to observe that as grape juice sat
Speaker 1: in vats and the natural yeasts turned sugar content into
Speaker 1: alcohol to make wine, you would give off bubbles as
Speaker 1: if it were somehow boiling without an external heat source.
Speaker 1: But anyway, so I was reading about fermentation in a
Speaker 1: in a book called the Noma Guide to Fermentation is
Speaker 1: written by the staff of the famous Nordic Cuisine restaurant.
Speaker 1: But there there are several ways they point out that
Speaker 1: you can define fermentation, which are basically all scientifically correct
Speaker 1: at different levels of zooming in the first is that
Speaker 1: fermentation is the transformation of foods by microorganisms. You let
Speaker 1: the microbes do something to the food. The second is
Speaker 1: that it's the transformation of foods by enzymes produced by
Speaker 1: the micro organisms. Specifically, what they're doing is they're participating
Speaker 1: in the chemical breakdown of molecules in the food. So
Speaker 1: they're breaking down long starch chains into different pieces of
Speaker 1: those chains, getting a little different sugar ers and things.
Speaker 1: They're breaking down long protein chains into smaller pieces of
Speaker 1: those chains. But then finally they say it is quote
Speaker 1: the process by which a micro organism converts sugar into
Speaker 1: another substance in the absence of oxygen and uh and
Speaker 1: as as we know that, there are different microbes that
Speaker 1: are involved in different kinds of fermentation. So for example,
Speaker 1: you've got yeast, which is a fungal microbe. It's a
Speaker 1: fungus and it's the agent primarily involved in the creation
Speaker 1: of bread, but also wine and beer. While the agent
Speaker 1: most important to the fermentation of vegetables like cabbage in
Speaker 1: sauerkraud and kim chi is lactic acid bacteria. And we'll
Speaker 1: get into more detail on that later, but the gist
Speaker 1: is that if you take a bunch of vegetables such
Speaker 1: as cabbage, doesn't have to be cabbage, but this is
Speaker 1: often the vegetable used you put salt on them, they
Speaker 1: will kind of whilt down, release water, create a brine
Speaker 1: that's salty in nature, and this salt creates an environment
Speaker 1: where certain kinds of bacteria that or 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 pH 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 a
Speaker 1: fallen fruit to the inturic fermentation inside a creature's digestive system. Yeah,
Speaker 1: and this is actually an evolutionary adaptation. Terreic 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 and use the help of a cultivated microbiome.
Speaker 1: They have chambers in their digestive system specifically for the
Speaker 1: microbial breakdown of tough plant matter, and it transforms all
Speaker 1: that grass and stuff like that into simple sugars that
Speaker 1: can be easily used as energy by the animals. So
Speaker 1: it's almost like these room and at herbivores have a
Speaker 1: kim chee jar inside their digestive system. But you know,
Speaker 1: if you've ever tried to make kim chee at home,
Speaker 1: which I am doing right now, one thing you know
Speaker 1: is that as the fermentation happens, you either need to
Speaker 1: have a ventable lid on the jar that will allow
Speaker 1: gas to escape, or you need to burp it frequently.
Speaker 1: You need to take the top off and let the
Speaker 1: gas out, or pressure can really build up with some
Speaker 1: disastrous consequences, which we can talk about at a little
Speaker 1: more later. And a similar thing actually goes on with
Speaker 1: animals that undergo terreic fermentation because these room and at
Speaker 1: herbivores end up having to burp out an awful lot
Speaker 1: of byproduct gas, generally methane, and in large enough quantity,
Speaker 1: which is generally the case with say cows that are
Speaker 1: that are that are raised by humans, that actually adds
Speaker 1: up and has an impact on climate. Yeah, that's absolutely right,
Speaker 1: And in fact, I know they're ongoing projects to try
Speaker 1: to fiddle with that, to say, like, can we actually
Speaker 1: get down the level of methane that is exhaled by
Speaker 1: these room and herbivores by making certain tweaks to say
Speaker 1: their gut microbiota or to there or to exactly what
Speaker 1: the sugars in their diet are and things like that.
Speaker 1: So that's cows. But when it comes to humans, and
Speaker 1: specifically when it comes to the intentional use of fermentation,
Speaker 1: of the fermentation process, this is widely considered a Neolithic technology.
Speaker 1: We're gonna take a quick break, but when we come back,
Speaker 1: we will dive into what we know of the history
Speaker 1: of fermentation. Than all right, we're back. So Robert, you
Speaker 1: you've teased us about the history of fermentation, saying that
Speaker 1: intend channel use of fermentation of foods by humans is
Speaker 1: something that goes back to the Stone Age, the Neolithic era, right,
Speaker 1: you know, at least uh So. Evidence of fermented beverages
Speaker 1: in China, for instance, seemed to date back to the
Speaker 1: seventh millennium BC, based on evidence from a Neolithic village
Speaker 1: in Henan Province uh and this this evidence revealed a
Speaker 1: a fermented mixture of rice, honey and fruit. This was
Speaker 1: mentioned in um in a in a paper titled Fermented
Speaker 1: Beverages in pre and Protohistoric China from P and A.
Speaker 1: S Uh in two thousand four written by A McGovern
Speaker 1: at all and then I was also looking at a
Speaker 1: two thousand and sixteen study from Adam Bothius in the
Speaker 1: Journal of Archaeological Science, and that puts a date on
Speaker 1: Scandinavian fermentation evidence to nine thousand, two hundred years ago
Speaker 1: during the early Mesolithic. UH. This would have been processed fish,
Speaker 1: so the idea here is that they were using something
Speaker 1: described as a gutter to ferment fishing and preserving it
Speaker 1: for later. The author discovered evidence of this gutter along
Speaker 1: with vast quantities of well preserved fish bones to support
Speaker 1: this argument, and fermented fish products are actually very common now.
Speaker 1: You might not know that you've been consuming them, but
Speaker 1: examples include Worcestershire sauce this is a fermented fish product,
Speaker 1: or of course, Asian fish sauces nonpla. These are made
Speaker 1: by salting fish and then using the extracted liquid that
Speaker 1: comes out as the strong, deeply complex salty flavoring agent.
Speaker 1: Another example would be an ancient Roman food known as garum,
Speaker 1: which was actually in many many ways similar to Asian
Speaker 1: fish sauce. So fermented fish products are are actually in
Speaker 1: wide use around the world today. You might not always
Speaker 1: think about them being the product of rotting fish, but
Speaker 1: or you know, controlled rot, but that's what they are. Yeah.
Speaker 1: And if you want more on garam and in in
Speaker 1: various fish fermentation in products sauces, we did an episode
Speaker 1: of Invention about ketchup and and how all this ties
Speaker 1: into the history of the product we now know as ketchup. Now.
Speaker 1: As for the fermentation of vegetables, that's key to what
Speaker 1: we're talking about here with kimchi, and it's believed that
Speaker 1: this too came before the agricultural revolution, so before we
Speaker 1: were able as humans to harness crop technology to control
Speaker 1: uh and manipulate the way crops grow for our benefit,
Speaker 1: we harness the power to preserve those goods through fermentation.
Speaker 1: This is fascinating and it reminds me of the evidence
Speaker 1: that we've discussed previously that the invention of bread probably
Speaker 1: predates the invention of agriculture, before wheat and other grains
Speaker 1: were staple crops that people grew on purpose. It looks
Speaker 1: like we have pretty good evidence that Stone age people's
Speaker 1: were harvesting wild grains such as iron corn, wheat, grass,
Speaker 1: taking taking those grains and then aching 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 bread crumbs there. So these
Speaker 1: would be bread, predating the agricultural revolution by thousands of years. Now.
Speaker 1: As for kim chi itself, so yeah, we we've already
Speaker 1: described it a bit and talked about it a bit.
Speaker 1: We're gonna do a little more detail here. There are
Speaker 1: a lot of fermentent items out there that we can
Speaker 1: compare to kimchi. But Joe, I don't I don't know
Speaker 1: if you'd agree with this, but I feel like, in
Speaker 1: many ways, there's nothing quite like it. Oh yeah, I mean,
Speaker 1: I love for minute vegetables generally, but kimchi is in
Speaker 1: a 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 now a cabbage Korean radish, made with
Speaker 1: a varying selection of traditional seasonings. Yeah, a very common
Speaker 1: preparation for kimchi would be you take nap a cabbage,
Speaker 1: you salt it to begin a wilting process that will
Speaker 1: bring water out of it, and then you prepare a
Speaker 1: brine or a marinade that will be made out of
Speaker 1: a Korean chili flake, often go chu garu, which is
Speaker 1: a red chili flake um, and then ginger garlic, often
Speaker 1: some kind of fermented fish products such as salted shrimp
Speaker 1: or fish sauce uh. And then other other ingredients such
Speaker 1: as maybe graded carrots, scallions UM. I might I might
Speaker 1: be leaving a few things out here, but but that's
Speaker 1: a pretty standard preparation. Now. I was reading about kimchi
Speaker 1: in the History of Korean go Chu Go go Chang
Speaker 1: and kimchi in the Journal of Ethnic Foods from and
Speaker 1: this was by Kwan at All and it points out that,
Speaker 1: you know, as you might imagine, fermentation in Korea began
Speaker 1: as a means of preserving vegetables, normally the Chinese cabbage,
Speaker 1: or MG cabbage as it is known today, It decomposes
Speaker 1: at normal temperatures due to the action of micro organisms.
Speaker 1: The authors here point out that specifically with with modern
Speaker 1: and kim chi, you add red pepper powder containing capsation
Speaker 1: to the cabbage, and this suppresses the growth of of
Speaker 1: putrifying bacteria and promotes lactic acid bacteria. The micro organisms
Speaker 1: here the author's right, grow and change into a form
Speaker 1: that humans can consume. Now, the basic process here is
Speaker 1: responsible for other key Korean fermented food products as well, uh,
Speaker 1: such as a go go chang, uh chion, gook chang,
Speaker 1: and doan jang. But one of the key ingredients in
Speaker 1: modern kimchi is the go chu, the Korean red pepper. UH.
Speaker 1: This powder, which again is involved in arresting putrification and
Speaker 1: leads to the production of lactic acid. And there are
Speaker 1: different varieties of go go chu. I think they're like
Speaker 1: four main categories. Now in terms of when the gochu
Speaker 1: peppers become involved in the process, apparently there I was.
Speaker 1: I was not really prepared for this, but apparently there's
Speaker 1: some back 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 just mentioned uh In that
Speaker 1: they contend that quote go chu started to grow on
Speaker 1: the Korean peninsula a few billion years ago, and it
Speaker 1: is safe to say it is original to Korea. So
Speaker 1: that's that is very much um uh in disagreement with
Speaker 1: with some of the information we're gonna get to here
Speaker 1: in a second, but I wanted to go ahead and
Speaker 1: put that out there. There's also apparently an argument that
Speaker 1: kim chi is less than a century old, with the
Speaker 1: pepper being introduced to Korea via Japan during World War Two,
Speaker 1: but this is strongly dismissed in many sources, including a
Speaker 1: two thousand fifteen paper by Jaying at All in journal
Speaker 1: Ethnic Foods, citing the Chronicle of the Three Kingdoms of
Speaker 1: Korea as a as an historical source dating kimchi back
Speaker 1: at least fifteen hundred years in Korean culinary tradition. The
Speaker 1: argument here is that it it would have been invented
Speaker 1: thousands of years ago. Uh and then but we see
Speaker 1: it at least some evidence of it fifteen hundred years ago. Yeah,
Speaker 1: Based on the historical sources I was reading, it seems
Speaker 1: like the most likely thing is that kimchi is definitely
Speaker 1: an ancient Korean food, but the introduction of peppers specifically
Speaker 1: is more recent, right, Yeah, that seems to be the case.
Speaker 1: So you don't you don't need, or you at least
Speaker 1: didn't need peppers for kimchi, uh, you know, throughout most
Speaker 1: of its history, but then you end up seeing the
Speaker 1: introduction of these peppers. I was reading The Colombian Exchange,
Speaker 1: A History of Disease, Food and Ideas by Nathan Nunn
Speaker 1: and Nancy Kuan, who point out that the peppers used here,
Speaker 1: the peppers alone, not the Korean fermentation traditions, etcetera, have
Speaker 1: a New World origin. So, uh, these peppers would have
Speaker 1: originated in areas of what is today Bolivia and southern Brazil.
Speaker 1: From there they traveled into Mesoamerica and the Caribbean before
Speaker 1: the arrival of Europeans, who then took it elsewhere. So
Speaker 1: along these lines, that's the Korean chili pepper was probably
Speaker 1: introduced to Korea in the early sixteenth century, and the
Speaker 1: actual kimchi tradition was much older, however, and seems to
Speaker 1: have its roots in Chinese pickling. And here's what Jay
Speaker 1: bock Park wrote about it in Red Pepper and kim
Speaker 1: she in Korea. In the Chili Pepper Institute paper from
Speaker 1: nineteen quote, it's thought that kim she may have originated
Speaker 1: from Chinese pickles. These pickles were brought to Korea and
Speaker 1: were altered into several types of kimchi to suit the
Speaker 1: taste of Koreans during the Sheila and Korea dynasties. That's
Speaker 1: c Through and cen Through 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 bitch 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 kimchi made that don't involve it, that might
Speaker 1: be known as like white kimchi, that might in fact
Speaker 1: be more similar to the older tradition that would of
Speaker 1: course involve salting the cabbage, It would involve adding flavorings
Speaker 1: to the to the brine or the marinade, but would
Speaker 1: but but don't bring in the hot peppers. Yeah, so,
Speaker 1: I know. I do want to stress though, that we've
Speaker 1: only briefly gone over the history here, but obviously we've
Speaker 1: 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, um,
Speaker 1: 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 kimchi is in Korean culinary culture. Uh. There's a
Speaker 1: two thousand six article on MPR as 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 when Napa
Speaker 1: cabbage and the 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 concerned 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 in gender love for your culture around
Speaker 1: the world. Yeah, yeah, share it with the world. And
Speaker 1: that's where you see initiatives like the Kimchi Bus. I
Speaker 1: don't know if you ran across articles about this. Um
Speaker 1: this was which was support it in some part by
Speaker 1: the South Korean government and it, you know, I don't
Speaker 1: think it's active right now, but it at least was
Speaker 1: traveling around to various countries and spreading traditional Korean food
Speaker 1: and kimchi um, you know, very very much spreading the
Speaker 1: word of kimchi. It's like an Iowa campaign bus for kimchi,
Speaker 1: Like the kimchi is gonna get out and give a
Speaker 1: speech now. That article from The Salt It also points
Speaker 1: out some other cool facts about about the culture of
Speaker 1: kimchi 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 a maide a large group of people.
Speaker 1: So it's not just you know, my household is making
Speaker 1: kim cheet today. It's no we we as a community,
Speaker 1: you know, or even we as you know, as people
Speaker 1: are making kim chee today. Well you know, I was
Speaker 1: telling you about this the other day actually that, uh,
Speaker 1: my experiments in making kimchi at home have been a
Speaker 1: solitary project so far. But I can absolutely see how
Speaker 1: making kimchi would be a really fun social, family and
Speaker 1: friends kind of project. Is something fun to do with
Speaker 1: kids because like the kids can maybe work on massaging
Speaker 1: the salt into the cabbage and massaging in the marinade
Speaker 1: between 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 funn 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 we have some sort of
Speaker 1: sauerkraut kit that just hasn't been used yet, you know,
Speaker 1: we've been eyeing, and so that might it seems like
Speaker 1: that might be usable for this process as well. Oh yeah,
Speaker 1: So to further clarify out there, what what I had
Speaker 1: been offering to share with Robert was was burp lids
Speaker 1: for jars, which I got, which allows you to, you know,
Speaker 1: in case you forget about the kimchi you've got going
Speaker 1: in the jar. It's not gonna blow the lid off
Speaker 1: or anything. It's got a little vent where if the
Speaker 1: pressure really builds up inside the CEO two can escape
Speaker 1: out the vent. Now, speaking of of pressure, I spaces
Speaker 1: this gets right Intoto. The next thing I wanted to
Speaker 1: talk about here that I know you were excited about
Speaker 1: as well, Joe. Yeah, and that's you have something as
Speaker 1: is culturally important as kimchi. UH. This is one of
Speaker 1: the reasons that kimchi has gone into space. So in
Speaker 1: two thousand eight, South Korea's Uh sillan Ye was selected
Speaker 1: to be the country's first astronaut, and the government apparently
Speaker 1: had worked nearly a decade to create UH kimchi as
Speaker 1: well as other Korean dishes they could potentially be taken
Speaker 1: into space that we're space ready UH for just such
Speaker 1: an individual. Now, as for why why take kim she
Speaker 1: into space? Well, okay, so there are a few different reasons.
Speaker 1: So one of them, of course, we again we've touched
Speaker 1: on the cultural importance of the dish. If you're sending
Speaker 1: an astronaut into space, that is not only a scientific endeavor,
Speaker 1: it is you know, it's about you know, national pride
Speaker 1: to a large extent, So it makes sense to want
Speaker 1: to send something as important as kimch up with them
Speaker 1: on an individual level. We've talked about this in the
Speaker 1: past concerning space food. You know that this is um.
Speaker 1: Going into space is a physically and mentally um you know,
Speaker 1: exhausting endeavor. So if you have something meaningful for them
Speaker 1: to eat up there, you know, some sort of bit
Speaker 1: some sort of food that that not only sustains them
Speaker 1: but perhaps reminds them of home, etcetera. Like that's that's
Speaker 1: that's a win. So there's been there's always been an
Speaker 1: effort to do that with the food that is sent
Speaker 1: up with astronauts. But then on top of that, micro
Speaker 1: gravity often is often described as us living in microscradic
Speaker 1: gravity rather as often described as being in this kind
Speaker 1: of state of perpetual nasal blockage, right, because everything is
Speaker 1: just kind of you know, without gravity, everything just kind
Speaker 1: of moves up and it just floats free. So this
Speaker 1: is one of the reasons that it's kind of difficult
Speaker 1: to taste food in space, and so you want something
Speaker 1: with a strong flavor perhaps spice to it, if you
Speaker 1: really want to to to taste anything. And that's one
Speaker 1: of the reasons that NASA's shrimp cocktail has apparently been
Speaker 1: popular for years, not because people want those you know,
Speaker 1: those shrimp that have been kind of stepped on orbit,
Speaker 1: but it's that it's the horse radish in the cocktail sauce,
Speaker 1: like it has a strong spicy flavor and it can
Speaker 1: kind of clear your head a bit, that's right. Yeah,
Speaker 1: it opens up those nasal passages. There's there's something there
Speaker 1: you can detect as as far as flavor and aroma
Speaker 1: goes um. But another thing I wanted to emphasize again, uh,
Speaker 1: the idea of a Korean astronaut having access to kim
Speaker 1: chi as part of their food in space. This is
Speaker 1: not just important because obviously it is part of Korean cuisine,
Speaker 1: but that it is such a regular part of traditional
Speaker 1: Korean culinary life that um, that kimchi. You know, it's
Speaker 1: not unusual for kim chi to be served at basically
Speaker 1: every meal on every on a Korean table, right, yeah,
Speaker 1: it is. It is the the traditional side dish, so
Speaker 1: you know it would be so in a similar sense.
Speaker 1: You know, it's like, of course there's ketchup in space
Speaker 1: or some version of it, because that is like the
Speaker 1: staple of some people's diets, right, Kimchi is very much
Speaker 1: the same affair. But the idea of taking kim chi
Speaker 1: into space, well, of course a wonderful idea as far
Speaker 1: as the flavor and the comfort that that it can provide.
Speaker 1: It immediately calls to mind some particular hazards in the
Speaker 1: case of kim chi that are not the case with
Speaker 1: other foods, because have you ever seen what happens when
Speaker 1: there is a sealed jar of kim chi without a
Speaker 1: burping lid, and the fermentation gets a little too aggressive,
Speaker 1: gets a little frisky. Uh, you should look up video
Speaker 1: of this, Robert. And so the microbes inside the fermentation
Speaker 1: will produce co O two as they do their business,
Speaker 1: and they can produce so much c O two that
Speaker 1: they can basically blow the lids off of jars, or
Speaker 1: maybe maybe if they don't blow the lid off, when
Speaker 1: you open the jar, suddenly it's like when you know,
Speaker 1: it's like mintos and a diet coke. It's like spewing
Speaker 1: spicy marinate everywhere, and the cabbage puffs up out of
Speaker 1: the top like you know, a muffin coming out of
Speaker 1: its mold, or like a Yorkshire putting. Uh. It can
Speaker 1: it can look really funny. And I've actually read stories
Speaker 1: of this being a real problem for people who have
Speaker 1: tried transporting kimchi in luggage and airplanes. I don't know
Speaker 1: if they let you do that anymore, but this at
Speaker 1: least has been a problem for some people. I've read
Speaker 1: about it in the past, Like you would take a
Speaker 1: jar overseas with you or something, and sometimes the jar
Speaker 1: can explode in your luggage and soak everything in spicy,
Speaker 1: rotting cabbage water, which is delicious but not really something
Speaker 1: you want to fully saturate your underwear. Um that that
Speaker 1: that article from the Salt that I mentioned earlier. They
Speaker 1: have a little bit more about the about taking kimchi
Speaker 1: into space, and they actually talked to youth astronaut about this,
Speaker 1: asking you know, what was it like? And the one
Speaker 1: thing they point out is that for the kimchee to
Speaker 1: go into space, it had to be radiated to kill
Speaker 1: all of the micro organisms in it, which he says
Speaker 1: left it looking quote so saggy. It looked like it
Speaker 1: was a hundred years old. So it apparently, you know,
Speaker 1: didn't taste maybe like terrestrial kimchi, but apparently it tasted
Speaker 1: it tasted enough like kim chi that it did the job,
Speaker 1: you know it um It It packed the you know,
Speaker 1: the spicy fermented punch, and it reminded them of home.
Speaker 1: So mission 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 kim chi is
Speaker 1: at its core a living product. And you can have
Speaker 1: kim chi that's been sterilized. I mean sometimes people sometimes
Speaker 1: I cook it before I eat it, especially when it
Speaker 1: gets older. You know, you can saute it in a
Speaker 1: pan and add as an as an ingredient of things,
Speaker 1: and then of course it's fantastic and delicious. But but
Speaker 1: at that point it is sterile before cooking it or
Speaker 1: before radiating it. If you've just got a jar of
Speaker 1: kim chie sitting in your fridge, I mean, this is
Speaker 1: a living organism. This, this kim chi that you're eating.
Speaker 1: The life goes on within it, and it will even
Speaker 1: though the fermentation will be much slowed down by the
Speaker 1: temperatures inside a refrigerator. Uh, it is still alive and
Speaker 1: things are still happening there. It is still maturing, it
Speaker 1: is still evolving as an ecosystem. Absolutely. Now speaking of
Speaker 1: that that ecosystem let's bring everything back down from space. Uh,
Speaker 1: not only to the Earth, but nder the earth. Because
Speaker 1: we've already referenced a few types of fermentation. Uh that
Speaker 1: entails burying a vessel or using some sort of a gutter,
Speaker 1: you know, made in earth or stone. It's worth noting
Speaker 1: that the traditional means of creating kim she also entails burying, uh,
Speaker 1: the the container bearing what Michael Pollen in his two
Speaker 1: thousand book Cooked described as a child sized earthenware croc.
Speaker 1: So I wanted to read just an excerpt from that,
Speaker 1: that excellent book, which, by the way, mentions kim she
Speaker 1: a lot. So if you if you're looking for, you know,
Speaker 1: a really good book about about foods, science and history,
Speaker 1: you know, of course always turned to Michael Pollan, but
Speaker 1: particularly this book has a lot of kimchi in it.
Speaker 1: But here's what he had to say. Quote. Nowadays, pit
Speaker 1: fermentation strikes most of us as primitive, strange, and unsanitary.
Speaker 1: Yet we think nothing of aging cheese is underground in caves,
Speaker 1: which is not so very different? And how different is
Speaker 1: a pit fermentation really from fermenting food in a croc
Speaker 1: earthenware as it's called, is really just earth once removed,
Speaker 1: cleaner and more portable, perhaps, but otherwise the same basic idea.
Speaker 1: Even today, Koreans bury their child sized crocs of kimchi
Speaker 1: in the backyard in order to maintain the even cool
Speaker 1: conditions that the lacto but silly prefer. The earthenware croc
Speaker 1: is a good reminder that every ferment is food and
Speaker 1: drink stolen or borrowed from the Earth by temporarily diverting
Speaker 1: its microbial gravitational pull to our own ends. Everyone knows
Speaker 1: who stole the power of fire from the gods for
Speaker 1: the benefit of humankind, But who is the prometheus of pickling?
Speaker 1: That sounds like a great story to where is? I
Speaker 1: would be shocked if there was not some mythical tradition
Speaker 1: that had a story of a god giving the gift
Speaker 1: of pickling or fermentation to humans. Yeah, it seemed I
Speaker 1: hadn't haven't had a chance to look into it. But
Speaker 1: I I would assume that some god or another would
Speaker 1: have that at least on their their resume, you know.
Speaker 1: For Pollen's part, he goes 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 apparently put it on par
Speaker 1: with fire in our history, saying like like pickling, um fermentation. Uh,
Speaker 1: these processes are up there with our fire technology in
Speaker 1: terms of their importance to our our our history. Well, yeah,
Speaker 1: I would say, especially if you go with Remember we
Speaker 1: talked previously about the importance of bread in the development
Speaker 1: of human civilization because of the kinds of nutrition that
Speaker 1: it could provide relative to its own ingredients raw. And
Speaker 1: of course fermentation is an important part of many bread
Speaker 1: so there are also unleavened breads. But you know, yeah,
Speaker 1: so I think it's there at the heart. I don't
Speaker 1: know if it's quite at the level of fire, but
Speaker 1: especially if you're going for like the richness of human
Speaker 1: life and pleasure and foods and all that, it's got
Speaker 1: to be right up there. Now, I do want to
Speaker 1: say something real quick about the idea of the prometheus
Speaker 1: of pickling. Now, in this case, I think pollen is
Speaker 1: using pickling a little bit informally, but there is a
Speaker 1: distinction to be made between pickling and fermentation. Basically, pickling
Speaker 1: is preserving food with a salt brine, while fermentation involves bacteria.
Speaker 1: So some pickled foods are also fermented, but they don't
Speaker 1: have to be. Yeah, Like, for example, you can make
Speaker 1: pickled foods that have no microbial action in them at all.
Speaker 1: Like you just dump a bunch of like vinegar and
Speaker 1: other flavors that you can make a pickle brine out
Speaker 1: of vinegar and salt and sugar or something like that,
Speaker 1: and it will be so vinegary that nothing will live
Speaker 1: within it, so there's no fermentation going on at all. Yeah,
Speaker 1: Like I do some of these box meals um uh,
Speaker 1: like you know Martha meals, etcetera, and uh, And they'll
Speaker 1: often have me do some like very quick fridge pickles
Speaker 1: or sometimes they don't even go in the fridge. And
Speaker 1: I have to say, sometimes I feel like I doubt myself.
Speaker 1: I'm like, am I really making something that I can
Speaker 1: call pickle? Or did I just throw some salt at
Speaker 1: some cucumbers for like ten minutes? Oh, you can call
Speaker 1: it a pickle. It's just not fermented. I mean, pickling
Speaker 1: is is a broader umbrella. Um. And and there are
Speaker 1: major differences in flavor. I'm sure you've noticed. Like you
Speaker 1: can achieve the same preservative effect either by salting cabbage
Speaker 1: allowing the lactic acid bacteria to thrive, which in turn
Speaker 1: produces lactic acid which lowers the pH of the environment
Speaker 1: and preserves the cabbage. Or you can just dump a
Speaker 1: bunch of acid like vinegar directly onto the food and
Speaker 1: just cut out the bacterial middleman. But you're losing a
Speaker 1: lot when you do that, because the bacterial middleman actually
Speaker 1: makes a huge difference in the aroma, taste, and texture
Speaker 1: of the final product. That the bacterial middleman produces a
Speaker 1: much greater diversity of flavorful compounds. Vinegar, pickled food, It's
Speaker 1: can be great. I like them sometimes, but they are
Speaker 1: fairly one note. Fermented foods, on the other hand, or
Speaker 1: very often described as funky and complex because of these
Speaker 1: wide ranges of of different flavorful compounds that come out
Speaker 1: of the microbial metabolism. Just one example, and there are
Speaker 1: tons of them. But for example, the cabbage fermentation process
Speaker 1: in many kinds of kim chi produces not only lactic acid,
Speaker 1: but compounds like diocetl which in other contexts. Diocetl is
Speaker 1: known to produce a distinctly buttery taste. Sometimes, for example,
Speaker 1: it's used as a flavoring in popcorn quote butter um.
Speaker 1: But this is one of the reasons that fermented vegetables
Speaker 1: like kim chi can sometimes take on these counterintuitively dairy
Speaker 1: reminiscent flavors buttery, nous, cheesiness, despite having no dairy content. Uh.
Speaker 1: And you might have encountered a similar flavor crossover from
Speaker 1: alcoholic beverages like wine, like if you ever had a
Speaker 1: a chardonnay that tay stood strangely like butter Uh. There
Speaker 1: could be multiple reasons for that, but a major one
Speaker 1: is diocetle. Diocetle from the metabolic processes of lactic acid
Speaker 1: bacteria in the wine could be partly responsible for that
Speaker 1: buttery flavor. And anyway, it's it's all of these metabolic
Speaker 1: byproducts of the lactic acid bacteria that that create this
Speaker 1: richness and complexity of flavor that comes along with lacto
Speaker 1: fermented vegetables like kimchi. Okay, we need to take a
Speaker 1: quick break, but when we come back, I'm going to
Speaker 1: be chatting about vegetable fermentation with Dr. Esther Miller. Thank
Speaker 1: thank We are back and now we're going to head
Speaker 1: straight into my chat with Dr Esther Miller, who studies
Speaker 1: fermentation and microbial ecology at a center called the Wolf
Speaker 1: Lab at Tufts University. Here we go. Esther Miller, thanks
Speaker 1: 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 insight
Speaker 1: and locust warming, and I moved to Sydney and looked
Speaker 1: at locusts in Australia. And then I became a high
Speaker 1: school teacher but with science, and then did work in
Speaker 1: a biotech company that also looked at the insect. So
Speaker 1: I did a sort of diverse range of things before
Speaker 1: um coming to do a PhD at Tough University. And
Speaker 1: it toughs you do rotations, and I did a bit
Speaker 1: of a project in the Wolf Club and I loved it,
Speaker 1: and I loved that it's uh ecology and so you're
Speaker 1: looking at how communities interact and how different populations interact
Speaker 1: is but it's very small. I can do it in
Speaker 1: the lab. I don't have to go across Australia gathering
Speaker 1: locust or anything like that. It's just on a blade
Speaker 1: in the lab. It's very simple. But it's also in food,
Speaker 1: and I really love food, and it was in cheese UM,
Speaker 1: and I love cheese, and you know, I moved to
Speaker 1: America from the UK and I didn't have access to
Speaker 1: good cheese. So the lab was a great place for
Speaker 1: um getting cheese. But I wanted to keep on with
Speaker 1: the plant research and that sort of background. So I
Speaker 1: asked Professor Wolf. I'm in the Wolf Lab. I asked
Speaker 1: Professor Wolf if I could start looking at microbial ecology,
Speaker 1: so the same things in the same questions that he
Speaker 1: was asking, but in um, sauer kraut and fermented vegetable products,
Speaker 1: and and he'll at me and it's um. It was great.
Speaker 1: So from there I started developing ecological questions in this
Speaker 1: fermented vegetable world. So one thing I can't leave off.
Speaker 1: You mentioned that you had done research with locusts. I
Speaker 1: was reading in another interview with you that I think
Speaker 1: was in Cooke's Illustrated a few years ago, that you
Speaker 1: you said that part of that research involved tickling the
Speaker 1: legs of locusts. But I was curious what what that
Speaker 1: was in service of studying. What were you trying to
Speaker 1: find out by tickling locust legs? Yeah, so, um, the
Speaker 1: desert locus, the cycle gagaria, which all of your listeners
Speaker 1: will know if they've ever been to a pat shop
Speaker 1: and looked at the lizard food. So the yellow and
Speaker 1: black locusts that hop around and you feed them to
Speaker 1: your lizards, that's the desert locusts. And they come in
Speaker 1: that dusky like they're sort of dark when they're adults,
Speaker 1: but they also come in bright green and it's the
Speaker 1: exact same species. It's the same thing. It just has
Speaker 1: a phase change where it goes from a solitary, beautiful
Speaker 1: grasshopper that's all alone eating, not hiding anybody, and then
Speaker 1: there can be a shift, um, and it's a serotonin
Speaker 1: spike that shifts until it becomes gregarious and they start swarming.
Speaker 1: So the research there it was Professor Steve Simpson was
Speaker 1: looking at how what is that shift, what is triggering
Speaker 1: that serotonin spike, and he found a few like agitate
Speaker 1: if they're jostling, if you sort of have them in
Speaker 1: a crowd, and they start knocking against each other. That's
Speaker 1: when that chemical shift happens. So it was simulating locust
Speaker 1: knocking against one another. So particularly yeah, yeah, you said
Speaker 1: you use the paint brush to tickle their news. So
Speaker 1: you tickle a locust leg for five seconds every minute
Speaker 1: for eight hours, and then it will have a completely
Speaker 1: different behavior. So the the parents takes a generation to
Speaker 1: come through, and it will be brown and yellow later on.
Speaker 1: But the behaviors, it goes from being uh, scared of
Speaker 1: locusts and running away to wanting to aggregate and like
Speaker 1: moving together. Did you have any interest in fermentation as
Speaker 1: food before you got into the science of it, particularly,
Speaker 1: I like, I like food, and so I think that's
Speaker 1: what drew me to the lab, as well as the
Speaker 1: strong emphasis on outreach. So it's very hard to get
Speaker 1: people excite did about bacteria and people are just like, oh,
Speaker 1: it's a disease, or wash your hands of of the
Speaker 1: use of antibiotics. But this is something that I can
Speaker 1: take a cheese or a jar of kimchi and talk
Speaker 1: to somebody about it, and I think, um, it became
Speaker 1: important to me to be able to talk to the
Speaker 1: general public about research. I think from a teaching background,
Speaker 1: finding a way that you can easily explain complex scientific
Speaker 1: ideas by being like, Hey, this cheese is like this,
Speaker 1: and why is it like that? And what is going
Speaker 1: on with this microbe and that microbe? Oh that's great. Yeah,
Speaker 1: this is like the sour krout can be a foot
Speaker 1: in the door to a to a broader view of
Speaker 1: the microbiological world. Yeah, and the cheese as well, Like
Speaker 1: you can you can take cheese anywhere and people will
Speaker 1: be excited because it stinks like it's immediately draws people
Speaker 1: in because you're like, hey, smell this, and then they're like, Okay,
Speaker 1: that's really growth. Um boy. I suppose you can do
Speaker 1: that with kimchi as well. Um. And so they have
Speaker 1: like smells and textures that are exciting, you know, totally. Um.
Speaker 1: So maybe you could start off by giving me sort
Speaker 1: of a character sketch of lactic acid bacteria as a group.
Speaker 1: What are these organisms, like, what do we know about them?
Speaker 1: And how do you think about them? So laticasi bacteria
Speaker 1: are a whole group and as many different species in
Speaker 1: this group. And then for the most part they are
Speaker 1: called grass generally regarded as safe. So the FDA doesn't
Speaker 1: really care about them. Um, there are in so many
Speaker 1: food products. The more you study, the more you find,
Speaker 1: So there's hundreds and you know, so they're not gonna
Speaker 1: go around saying this one is safe and this one
Speaker 1: and this one. They're just as a blanket they're safe.
Speaker 1: Um there are in so many foods. Um And as
Speaker 1: a rule, they take sugars and they ferment them into
Speaker 1: lactic acid. That's pretty much the basics. Some of them
Speaker 1: are a little more complex, and they'll turn things into
Speaker 1: actic acid and um acetic acid and CEO two and
Speaker 1: so those are the hatero fomentius. They do more than
Speaker 1: one thing, so you sort of think they're making two
Speaker 1: different assets, whereas the home of fermentus they're just doing
Speaker 1: one thing. They're just making lactic acid. And that's the
Speaker 1: two big groups when you're thinking about lactoc acid. And
Speaker 1: if I ever call them LBS, it's laptic acid vecteria.
Speaker 1: So we know that lactic acid bacteria are one of
Speaker 1: the major players in uh in vegetable fermentations like kim
Speaker 1: chi or sauer kraut. But could you give us a
Speaker 1: broader picture about what's going on in the whole life
Speaker 1: cycle 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 souer cut, I think souer crt is under
Speaker 1: utilize compared to sour dough. But if you've done any
Speaker 1: fermenting of soun cut, which I think is shared, um,
Speaker 1: do you know that you don't add a starter So
Speaker 1: that's sour door. When you first do the starter culture,
Speaker 1: you're just relying on the natural who is there to
Speaker 1: inoculate the ingredients. So you take cabbage or if you're
Speaker 1: making kimchi, other ingredients, or you can make other fermats
Speaker 1: like adding in carrots or whatever, and the bacteria these
Speaker 1: light to Casa bacteria just present on the surface. But
Speaker 1: the one the first thing that I did in my
Speaker 1: project was paid out the cabbages, and I found that
Speaker 1: light to Cassa bacteria really low. If you're looking at
Speaker 1: the bacteria present on a vegetable. There are lots and
Speaker 1: lots of um proteo bacteria, many many things like pseudomonas
Speaker 1: um spinglemona. So these are bacteria that like living on
Speaker 1: plant le and for the most part, they're really beautiful
Speaker 1: and colorful because they contain pigments that protect the bacteria
Speaker 1: from UV light. So if you think of a cabbage
Speaker 1: out in a field, it's actually exposed it really really
Speaker 1: high levels of UV light, and it doesn't have a
Speaker 1: lot of water accessible on the leaf surface. So leaves
Speaker 1: are normally covered in a waxy film, and so there's
Speaker 1: not a lot of nutrients, there's not a lot of water.
Speaker 1: It's really hard to survive. And the bacteria that are
Speaker 1: there have a lot of pigments and ways that they
Speaker 1: can adhere to the surface of the plant and help
Speaker 1: them survive. And it's not really the lactic as of
Speaker 1: bacteria's way of living. They're not really high but like
Speaker 1: very abundant on the leaf. But when you chop that
Speaker 1: leaf up to make your sua crowd, you're releasing those
Speaker 1: punch sugars. You're making them like very readily available. And
Speaker 1: then when you add the salt, you further draw out
Speaker 1: those sugars, and you completely change the playing field. So
Speaker 1: you've gone from a high oxygen, highlight, low nutrient condition
Speaker 1: to all the nutrients in the leaves are out and
Speaker 1: slashing about. You take away the oxygen when you push
Speaker 1: it down into a messenger, and you add salt, and
Speaker 1: this is really really strong abiotic selective pressure that will
Speaker 1: change who can live. And that's when the lactic asa
Speaker 1: bacteria really come into their own and they can start
Speaker 1: increasing in abundance. Now I mentioned earlier the two big
Speaker 1: groups of lactic asa bacteria, the petro fermentors and the
Speaker 1: homo fermentors. So at the very start of fermentation, we
Speaker 1: get a massive increase in the hetero fermentors. So that's
Speaker 1: things like lucona stocks and ver clia 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 true phase. I wish I had a white water.
Speaker 1: You can 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 lower is the pH even more.
Speaker 1: And as the pH falls um, those 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 fermentation. 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. Oh, I'm sorry, did I
Speaker 1: say bacteria. Sorry, I didn't mean to say that. The
Speaker 1: lactic acid. Yes, yeah, yeah, exactly, yes, And actually lactic
Speaker 1: acid is a less harsh acid. So if it was
Speaker 1: just fermented by hetero fomentors and it just we ate
Speaker 1: a sourer krout that was just made with a seedic acid,
Speaker 1: it wouldn't be that nice. It would be very very
Speaker 1: it would be like a very harsh like a pickle,
Speaker 1: Like you wouldn't eat all of the pickle juice because
Speaker 1: it's very vinegary um. But when you have sour krout,
Speaker 1: it should have a softer, buttery flavor. So you have
Speaker 1: to sort of trust me on this one and go
Speaker 1: home and eat some and compare it to just straight pickles,
Speaker 1: which are quite acidic, because that lactic acid has a
Speaker 1: softer um like, it's not as shark. Yeah, that's definitely
Speaker 1: something you notice is a difference between quick pickled foods
Speaker 1: that you use vinegar to pickle versus fermented foods where
Speaker 1: it comes from the back to it's a much more soft, round,
Speaker 1: complex kind of flavor. So so normally when you ferment
Speaker 1: vegetables and uh, and you're trying to you know, you
Speaker 1: salt them, you make a brine, and you encourage the
Speaker 1: lactic acid bacteria. You said, you see these two broad
Speaker 1: spikes with the hetero fomenters and then the homo fomenters um.
Speaker 1: But even within that, you're still going to see a
Speaker 1: lot of different species involved, right, that there can be
Speaker 1: widely different profiles of what exact lactic acid bacteria are
Speaker 1: taking over. Is that correct? Yes, there's a lot so
Speaker 1: UM looking at who's there, there's just some big players,
Speaker 1: so they'll be like lacto, basilis, bravis in basically everything
Speaker 1: at a really high percentage, and then there'll be a
Speaker 1: lot of UM low numbers of many other ones. So
Speaker 1: we've just recently done a survey of North American fermented
Speaker 1: vegetable products UM, which I was really excited about because
Speaker 1: there's a lot of research on UM Asian products. So
Speaker 1: there's a whole research institute of kimchi in Korea, and
Speaker 1: there's UM a lot of research in Europe. But this
Speaker 1: is the first United States Sauer Kraft survey and we
Speaker 1: found on average teen point eight species of lactic gas
Speaker 1: of bacteria her jar. But most of them are some
Speaker 1: of the really common laticas of bacteria. They take they
Speaker 1: take up the bulk. So would you find any noticeable
Speaker 1: differences in in like aromas or flavors produced depending on
Speaker 1: what the microbial ecosystem in the fermented jar vegetables looks like?
Speaker 1: I haven't. I haven't done any specific research on that,
Speaker 1: but I haven't myself noticed anything. I think there can
Speaker 1: be a big difference between kimchi and sauerkraut, which is
Speaker 1: hard to measure in terms of the bacteria that are
Speaker 1: present because there's so many other flavors going on. So
Speaker 1: some kim cheese are fermented at a lower temperature, and
Speaker 1: when you of fermenting in a really cool temperature, like
Speaker 1: between ten to fourteen degrees celsius, you're promoting those hetero fermenters,
Speaker 1: so you get a different flavor. So there can be
Speaker 1: a lot of asalia in kimchi, which is less prevalent
Speaker 1: in souer crawl like, They'll still be there but in
Speaker 1: lower numbers. But it's very hard to compare the flavors
Speaker 1: and attribute that to the bacteria when you've also got garlic, ginger,
Speaker 1: red pepper and everything else. That's one thing I found
Speaker 1: hard in doing the survey is that every producer might
Speaker 1: have different vector, but they all have like their slight
Speaker 1: tweaking of recipes, so some had like caraway seeds or
Speaker 1: they throw in an apple just like So you mentioned
Speaker 1: that that the lactic acid bacteria tend to be found
Speaker 1: in very low numbers. If you just takes a raw
Speaker 1: leaf of cabbage from the farm before fermentation. So we're
Speaker 1: do we have any idea about where these microbes generally
Speaker 1: come from. Is it just something that's probably there on
Speaker 1: a leaf of cabbage even though it's in very small numbers,
Speaker 1: and then the fermentation environment helps those numbers bulk up
Speaker 1: over time, or there are other possible vectors. Yeah, So
Speaker 1: I went out to farms or common gardens um in
Speaker 1: the summer of sen and tried to find environmental sources
Speaker 1: of Lactica Sa bacteria. So I took soil and leave
Speaker 1: examples and not cabbage leaf um, wead leaves and things
Speaker 1: that were just growing next to crop plants um, and
Speaker 1: I found that they had pretty low levels of lactic
Speaker 1: as bacteria. So I didn't find like a big environmental
Speaker 1: reservoir of these bacteria, which I think it's pretty incredible
Speaker 1: that we know so much about them in the human
Speaker 1: micro like the human got microbiome and in probiotics and
Speaker 1: probiotics and fermented foods, but very little is known about
Speaker 1: their pology, and I couldn't find too much. I think
Speaker 1: I definitely talked about it in the in a previous
Speaker 1: podcast about maybe they're being affected in by insects. If
Speaker 1: you are USU papers where honey bees have let to
Speaker 1: gas a bacteria and that guy um and they're very
Speaker 1: specific two bees though, I think because bees taken nectar
Speaker 1: and then the sugars in the nectar can get broken
Speaker 1: down by lack to gas of bacteria. But I haven't
Speaker 1: yet found any evidence that the insects and the insect
Speaker 1: droppings go on to be the source of lack to
Speaker 1: Gasa bacteria and fermented vegetables. So perhaps a very small
Speaker 1: amount of lack to Gasa bacteria in soil can then
Speaker 1: try and like dispersed onto cabbages repeatedly, and then maybe
Speaker 1: it's just low levels everywhere it's it's still a puzzle.
Speaker 1: Is it possible also that some amount of it just
Speaker 1: comes from the kitchen environments or other environments where this
Speaker 1: where fermentations are prepared, that it's on jar as, it's
Speaker 1: on spoons and all that kind of stuff that's been
Speaker 1: sort of talked about a lot, and I'll have to
Speaker 1: look up the name for you, but there was a
Speaker 1: recent paper where they looked at a saddle crowd facility,
Speaker 1: so they I think it 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: to cast a bacteria in the environment. They only found
Speaker 1: levels on the cabbage. But if you're thinking about making
Speaker 1: sadle crowd in a facility, you're gonna 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 always have some amount of l to casper to
Speaker 1: you now, was I reading that previously you did some
Speaker 1: research with trying to grow sterile cabbage in order to
Speaker 1: to inoculate it with bacteria and see how the bacteria
Speaker 1: did on it. Yeah, I'm very excited about it. It It
Speaker 1: came out in the Journal of Visualized Experiments, and then
Speaker 1: I couldn't film because of COVID. But they will be
Speaker 1: coming in on Wednesday. Um, but I managed to grow
Speaker 1: cabbages and I can send you pictures. Um, I managed
Speaker 1: to grow cabbages in glass tubes and they are sterile
Speaker 1: as far as I can tell. Like you know, maybe
Speaker 1: there's some media that one bacteria could grow on, but
Speaker 1: as far as we can tell, they're completely sterile, and
Speaker 1: they're happy, and they're growing in calcined clay. You can
Speaker 1: articulate that. So if you put in the articlave, high heat,
Speaker 1: high pressure, will be sterile at some nutrient broth and
Speaker 1: they're really happy. And now did that research involve you
Speaker 1: trying to see what kind of environment those previously sterile
Speaker 1: cabbages would make for different microbes or was that just
Speaker 1: to study the cabbage itself and how it could how
Speaker 1: well it did without a microbiome. No. I wanted to
Speaker 1: do actual competition experiments with large caste bacteria and the
Speaker 1: philosphere microbiome. So the philosphit is the community of bacteria
Speaker 1: living on a leaf. So I wanted to say, well,
Speaker 1: maybe like to cast a bacteria in low abundance because
Speaker 1: they need a particular microbe to grow with, or there's competition.
Speaker 1: So I made all of this sterile cabbage. It took
Speaker 1: me years and then I inoculated it with lead casa
Speaker 1: bacteria and they don't grow. Like if you just spray
Speaker 1: a cabbage with lack to caste bacteria and it's happy.
Speaker 1: You don't put any other thing in there to compete
Speaker 1: with it, it won't grow. The cabbage are the lactic
Speaker 1: acid bacteria. The cabbage is fine. The cabbage I wasn't interested.
Speaker 1: I haven't done any measuring of cabbages or their growth. Um,
Speaker 1: they do fine with or without a microbiome. I sprayed
Speaker 1: some yeast on cabbages once and they didn't enjoy that.
Speaker 1: The cabbagies went brown and just with it. But bacteria
Speaker 1: fine on cabbage. They don't influence the cabbage. But yeah,
Speaker 1: I did twenty bacteria that you just naturally find on
Speaker 1: a cabbage and things like the uh pseudomonist that I mentioned,
Speaker 1: So things like that, I sprayed them on the cabbage
Speaker 1: and they will increase. You will see like they're happy
Speaker 1: growing on a cabbage. The lattic as a bacteria tank.
Speaker 1: So it's very hard to do an experiment with something
Speaker 1: that won't grow, like I mix it with other things.
Speaker 1: They grow Bacteria gus wow, Uh, so we know that
Speaker 1: obviously these lactic acid bacteria are the main player and
Speaker 1: vegetable fermentations, but there are fungal microbes like yeast, so
Speaker 1: we've mentioned a little bit that are major players and
Speaker 1: other kinds of fermentation of course, in like bread or
Speaker 1: in wine or beer. Did you mention over our email
Speaker 1: that um that in looking at store bought preparations of kimchi,
Speaker 1: you've found yeast in some of them. That seems kind
Speaker 1: of surprising. Yeah, So I tried really hard to find
Speaker 1: some literature on this, and you only see a few
Speaker 1: papers from a long time ago stating that yeaster um
Speaker 1: sometimes found as spoiler organisms. But when I did this
Speaker 1: North American sour krout survey or fermented vegetable product survey,
Speaker 1: so it is sour kart's and kim cheese, I found
Speaker 1: over half of them had yeast, like a lot a
Speaker 1: lot of yeast, Like some of them had more counts
Speaker 1: of yeast than bacteria, which was really surprised by. So
Speaker 1: the back the use that I found is safe. There
Speaker 1: are things like kazakhstania, which you do find in sour dough,
Speaker 1: so they're not they're not toxic. But everything that you
Speaker 1: read says there undesirable and fermented vegetable products because they
Speaker 1: give musty, yeasty, sort of dankish flavors, I guess, and
Speaker 1: they can form a film, which I think it's pretty
Speaker 1: offputting if you're trying to create a new product that's
Speaker 1: covered in a yeast film. Yeah, you want your cut
Speaker 1: smell like skunky beer. No, definitely not. It's already yes,
Speaker 1: a tough sull. I when I had this, I had
Speaker 1: fifty one jars and I was delighted and I was like, hey,
Speaker 1: who wants some? And I would open I opened and
Speaker 1: sampled them all in the conference room. It's smaller rooms
Speaker 1: and they's a tough and people were not happy. They
Speaker 1: were like, wow, the whole rooms stank for a week.
Speaker 1: I think it's just in an enclosed space. Opening fifty
Speaker 1: one jars of sauer kraut and kimshi was a little much,
Speaker 1: but yeah, and I tried to eat them all, but
Speaker 1: I I really couldn't. That's that's a lot. But you
Speaker 1: couldn't eat fifty jars of kimchi by yourself, or sauerkraut
Speaker 1: and kimchi. No, I tried so hard. I can do it.
Speaker 1: And part That's why I wrote the grant. I was like,
Speaker 1: now I can get to eat all of it. If
Speaker 1: I write a grant that says I need to buy them, 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: kimchi 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 kim
Speaker 1: chi for years, and I've always put off trying to
Speaker 1: make it because it seemed like a scary, daunting, potentially
Speaker 1: dangerous procedure if you're fermenting things and you don't know
Speaker 1: what you're doing. But honestly, i've I've found it easier
Speaker 1: than I expected it to be. So I guess one
Speaker 1: thing a lot of people are probably wondering is how
Speaker 1: safe is it to experiment with making sauerkraud or kim
Speaker 1: chi or some other lacto fermented vegetable. Is this something
Speaker 1: that's probably gonna poison you if you screw it up,
Speaker 1: or is it pretty forgiving. That's a great, great question
Speaker 1: because I think people are really scared and when people
Speaker 1: come over there, because I have a lot of fim
Speaker 1: it's on my friends these days, but they're actually pretty safe.
Speaker 1: Anything that's anaerobic, um, you're really really making it very
Speaker 1: hard for things like et coli and my steria to grow,
Speaker 1: So they're pretty safe if you do get the anaerobic
Speaker 1: conditions correctly. So sometimes if you're fermenting in a massenger
Speaker 1: and you have like a pocket of air on the top,
Speaker 1: you'll notice the very top layer of your ferment might
Speaker 1: be a little off, and then you can just take
Speaker 1: that off and then push it down so it's submerged.
Speaker 1: But probably not an official thing to say, so basically,
Speaker 1: as long as you've got the salt there and the
Speaker 1: stuff's underwater, it's it's going to be safe. Yeah. I
Speaker 1: think that's one thing that I found remarkable with everything
Speaker 1: that I've done, with everything that I've read. I think
Speaker 1: that's why I just love this project so much, because
Speaker 1: it seems so haphazard, like you're just taking random ingredients
Speaker 1: and salt, and yet it works so consistently um worldwide.
Speaker 1: You know, That's what blows my mind. The things that
Speaker 1: we found in this North American survey are the exact
Speaker 1: same things that they find in Europe, to the exact
Speaker 1: same things that they find in everything in Asia. So
Speaker 1: you're like, it's so robust. Broadly, what do you find
Speaker 1: amazing about fermentation? Well, that bacteria that we don't know
Speaker 1: how they where they live in. We can't find them
Speaker 1: in the environment get into everything that we eat, and
Speaker 1: a consistent Like, it's amazing we can't track them. But
Speaker 1: all over the world there's it's the same species and
Speaker 1: you can't follow it from a field to a cabbage.
Speaker 1: You know, that's amazing. That is amazing. Uh, I don't know.
Speaker 1: It's one of the things we actually love to talk
Speaker 1: about on this show is kind of the hidden realities,
Speaker 1: the things that are so important to human culture but
Speaker 1: that you know, you wouldn't be able to see them
Speaker 1: looking at I mean, I guess you don't see any
Speaker 1: microbes with your eyes normally unless they're starting a really
Speaker 1: big colony. But but even with scientific instruments, like you
Speaker 1: don't know where all these microbes are coming from. Yeah,
Speaker 1: it's amazing. Like I was trying to write a review
Speaker 1: on dispersal, like how do how does the bacteria get
Speaker 1: from here to that? And you can read about the
Speaker 1: moving miles and thousands of miles on wind. It just
Speaker 1: gets in the wind and just dispersed. But you you've
Speaker 1: got no way of really knowing unless you sort of
Speaker 1: make genetically modified bacteria and release them, which I'm not
Speaker 1: going to do. But you know, like, how could you
Speaker 1: know if there's bacterias that, because they're so small, you'd
Speaker 1: never tracked them. I think it's amazing. So is there
Speaker 1: anything else you've been working on recently that you wanted
Speaker 1: to talk about? Well, I was gonna say, and I
Speaker 1: forgot to mention that I am doing a community assembly experiment.
Speaker 1: So I've got three yeast and three bacteria that were isolated.
Speaker 1: Most of them were isolated from that Sauerkroud survey. So
Speaker 1: I took the bacteria that I found in that survey,
Speaker 1: and I'm competing the yeast and the bacteria together in
Speaker 1: little jaws of sterile vegetable extract two, and I've put
Speaker 1: them under different conditions, like different temperatures, different salt concentrations,
Speaker 1: um and using different cabbage extracts a red cabbage, grain cabbage,
Speaker 1: and Napa cabbage to see if any of those influence
Speaker 1: the presence of yeast. And actually, I think it looks
Speaker 1: like the temperature that I fermented at could be influencing
Speaker 1: the abundance of yeast. So at higher temperatures, perhaps you
Speaker 1: get more yeast. So maybe the North American fermenters are
Speaker 1: using different conditions and that's why the ferments have more yeast.
Speaker 1: But I'm still working in it. Interesting. So, if if
Speaker 1: you're making kimchi at home or making sarokrawd 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
Speaker 1: in it, it can go horribly wrong. The pH just
Speaker 1: doesn't fall as much because tried that, and I was
Speaker 1: even adding LA to Casa 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 lactic acid
Speaker 1: 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 filted vegetable extractures, you know, so just completely sterile
Speaker 1: media and adding LA to CASA bacteria in the east,
Speaker 1: So they allowed to Casabactero didn't have that much competition,
Speaker 1: you know, they're there with the East, and yet they
Speaker 1: still didn't do that well when there's no salt. Mm hmm.
Speaker 1: So maybe the salt is even helping it in some way.
Speaker 1: I think there's got to be something going on with
Speaker 1: the salt as well. M m, well that's very interesting. Alright, Well,
Speaker 1: I think we have to call it there. But thank
Speaker 1: you so much for joining us today. This has been
Speaker 1: so great and we really appreciate you sharing your time
Speaker 1: and your expertise. It's been a lot of fun. Yeah,
Speaker 1: thank you very much for having me. Well, I guess
Speaker 1: that wraps up this episode, but once again, huge appreciation
Speaker 1: to Dr Esther Miller for taking the time to speak
Speaker 1: with us. And I will say, though this episode is over,
Speaker 1: there is that whole hidden world flowing into the fermentation jar.
Speaker 1: So it's possible that we may have to come back
Speaker 1: and 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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