Stanford Fermented Food Conference: Highlights

The two-day Stanford Fermented Food Conference comprised of 24 presentations with PowerPoint slides. These highlights are a selection of quotes from the presentations that I found particularly interesting. Links to the presenters bios and head shots can be found on the Conference Preview posting. This is the 8th and final post specifically about the conference. Be sure to scroll back in Booch News to read the others.

Justin Sonnenburg: Welcome

We have an amazing group assembled here, we have scientists, we have chefs, we have anthropologists, we have clinicians, fermented food makers, fermented food enthusiasts. So really, it’s just an incredible group that we’ve brought together, very much like a spontaneous fermentation. And I will try to suppress the puns and analogies for a little bit. But I am a dad, so I am in a bit of a pickle.

Rob Dunn: Introduction

Melville says something in of Moby Dick to the effect that the whale sees a different sea from each of its colossal eyes. And so one of the things I’m experiencing in these conversations already today is that we’re bringing very different perspectives to fermentation, which is more things than we think it is, and that we don’t have to reconcile them.

[The quote in full reads:]

“From this peculiar sideway position of the whale’s eyes, it is plain that he can never see an object which is exactly ahead, no more than he can one exactly astern…The peculiar position of the whale’s eyes, effectually divided as they are by many cubic feet of solid head, which towers between them like a great mountain separating two lakes in valleys; this, of course, must wholly separate the impressions which each independent organ imparts. The whale, therefore, must see one distinct picture on this side, and another distinct picture on that side; while all between must be profound darkness and nothingness to him..” – Herman Melville, Moby Dick, Ch 74

Aviaja Hauptmann: An Arctic perspective on fermentation

The macronutrient composition of the traditional Greenlandic diet was comprised of 55% fat energy and 45% protein energy. So essentially, no plants at all. Our diet is an animal source diet. Sea mammals are the cornerstone of the Arctic diet. The seals, the whales. And you can ferment those in many, many different ways. You can ferment the blood, the flippers. You can ferment the meat, the intestines. There’s a lot of different ways to ferment sea mammals. But we also eat land mammals, birds, fish, and shellfish. You can ferment those as well. You can ferment whole birds, but you can also ferment the eggs.

The eating of intestines and intestinal content is also eating a food that has been fermented. And it’s a practice that was very common in the Arctic. And the fermentation practices here, you don’t add salt. You don’t really add anything. You rely on what’s already there in the food, and the sun, and the weather, and the temperature.

[This 40-minute 2001 online presentation to the Fermentology Seminar Series from the Department of Applied Ecology at North Carolina State University covers much of the same ground as her Stanford talk.]

Veronica Sinotte: ArcheoFermentation—biomarkers of ancient yogurt reveal past foods across cultures

If the nomads want to make yogurt and cannot find enough starter culture, they crush the tiny eggs of the ants sheltering under the stones in their palms. When you put this into the milk, that milk becomes yogurt. In neighboring Bulgaria, a traditional spring practice involves fermenting yogurt within a red wood ant colony.

Rob Dunn: Cultivating mutualism with other species

The honeyguide is this amazing and drab but wonderful bird. It’s across sub-Saharan Africa, and it has this sort of fundamental lifestyle constraint, which is that it loves to eat wax, and it has no way to get to wax on its own. It has an amazing nose. It can smell wax. It can smell honey-bee hives, but it actually can’t get into them. And so I don’t know about the culinary version of this, but maybe it’s like wanting to go to Mugaritz but not being able to afford Mugaritz. And so what the honeyguide has figured out how to, evolved the ability to, go to human communities and to sing a specific song and fly a specific flight that says, “For the love of God, I found a honey bee hive. If you would just follow me, you can get all the honey, which I know that you like, and I want the wax.” This emerged a long time ago as an invitation from the honeyguide to humans.

[This hour-long 2023 video, part of the Fermentation and Health Speaker Series from the Sonnenburg Lab, introduced by David Zilber, covers some of the same ground as his Stanford talk.]

Jo Webster: Open Mic

Something you might want to consider is that there is World Junk Food Day, there is World Emoji Day, and now another idea of mine, we have World Ferment Day, on February 1^st. The first one happened this year, and the key aim of this day is to get more fermented foods into the mouths, or at least into the hands of more people.

Matt Carrigan: Human ancestors adapted to consume fermented fruit, probably

We know from the archaeological record, that humans have been intentionally making alcoholic beverages for about 10,000 years in various parts of the world. Of course, ever since angiosperms started making fruits 80 million years ago or so, we have nature probably doing something of the same sort. So maybe there’s some good side to alcohol consumption. There’s an emotional reward system that is activated by ethanol, and that would perhaps be true of other animals, and that could be good. You might change your risk calculus when your mind is altered, and that might unlock new territories that you explore and find good things. We do know from fruit flies that it also changes mate preference in females.

Did we adapt to consuming fermented fruit? I think so. Primarily so we wouldn’t get drunk and fall and hurt ourselves. We still get the benefits.

Christina Warinner: Archaeogenomics and the future of heirloom microbes

When it comes to Mongolia, what a lot of people don’t appreciate is that people faced these huge challenges in the past. The Eurasian steppe zone was inhospitable. It just grows grass. We can’t eat grass, so hunter-gatherers would follow certain herds. They could follow riverine corridors, but the great Eurasian interior was inaccessible to humans until the invention of dairy pastoralism. Suddenly you could move those animals across the open steppe, not just the river corridors, and you could utilize everything, and that’s when human populations really start expanding. In places like that where you could not perform agriculture or in really arid water-stressed environments or desert environments, dairying is this amazing solution. We sometimes forget about in the era of global food chains and refrigeration that people didn’t have access to that, and this was a really successful adaptive strategy.

The earliest evidence of milking in Mongolia dates to about 5,000 years ago, where it starts with cattle, sheep, and goats, so it’s a ruminant-focused milking. Sheep make up the most important milk in the beginning, and then you get cattle and goats later. We get horses for the first time. That happens during the Late Bronze Age, and then becomes really important during the Iron Age. Horses become really important because, of course, they have very high lactose levels, and so make really excellent alcohols. And then later we get things like camel milking and even yak milking that are only introduced during the Medieval Period.

[This hour-long 2024 presentation to the Harvard Radcliffe Institute covers much of the same ground as her Stanford talk.]

Erica Sonnenburg: Can fermented food improve the industrialized gut microbiome?

Part of why the microbiome is so interesting from a biomedical perspective is that it’s highly malleable. So unlike our human genome, which there’s not a whole lot we can do about at this point, our microbiome is malleable, so you change your diet, change your lifestyle, you can change the microbes that are in your gut and what they’re doing, and that can be a really powerful lever on our post-biology. Everyone’s microbiome is a little bit different, and so understanding how to change the microbiome or maximize it in some way can be an important aspect of precision health.

A lot of the genes that are enriched in industrialized populations are genes that are involved in redox sensing and antioxidants. This is an indication that our microbiome, our gut, there’s excessive oxygen, and so our microbiome has to encode these genes in order to deal with this oxidative stress. And these are all signs of inflammation. So yes, we have a microbiome that’s adapting to our environment, but our environment is a gut that’s inflamed. We also can see that in American stool, we just have much less of these short-chain fatty acids that are very important in immune regulation and keeping inflammation down.

[This 90-minute 2025 video covers much of the same ground as her Stanford presentation.]

Paul Cotter: Fermented foods—harnessing their potential to modulate the microbiome gut-brain axis

Imagine how confusing it is for somebody who’s going to a supermarket and thinks that they’re buying kefir, and that they’re consuming a true artisan product that’s reflective of a product that’s been made over history. And really what they have is something to which a couple of staphylococcus have been added or to which a few probiotics or some other sort of strains were added after the fact.

[This half-hour 2021 video, recorded as part 2 of a ‘Gut Health Gurus‘ podcast series, covers some of the same ground as his Stanford talk. Specifically, at 9:50, he discusses the contents of various commercial milk kefirs compared to artisanal home made kefir.]

Andrew Luzmore: Understanding the impact of cold stress in fermented winter vegetables

What else can we look at in the fermentation economy that tries to make this connection between the different agricultural conditions and fermentation metrics? What about wheat? What about soy for miso? What about tea for kombucha? But more broadly, how can agricultural decisions intentionally influence fermentation?

Josh Evans: Frontiers in fermentation practice and theory

We’re not just making new flavors, we’re really opening up new niches for new life to emerge. We extended this work to the International Space Station. And we sent this research to the ISS to see, first and foremost, if fermentation in space was possible, and if so, how it might compare to that on Earth. How does a novel environment like space, where there’s increased cosmic radiation, there’s microgravity, how does that affect these fermentation processes that we already don’t even know that much about on Earth? What we found is that, well, first and foremost, it should be said that it fermented. It made a miso. It was safe and successful. But beyond that, we also found a few key differences in its microbiology, in its chemistry, in its sensory profile. And all of these together suggested that the space environment shapes fermentation in some distinct ways, or what we came to call space terroir.

[This hour-long 2023 video, anoter of the Fermentation and Health Speaker Series from the Sonnenburg Lab, features John in conversation with David Zilber, Elisa Caffrey, and Justin Sonnenburg. It covers some of the same ground as his Stanford talk.]

Maria Marco: If and how fermented foods improve health

We wanted to look at the impact of the metabolites in sauerkraut in barrier function, and why this is important is that our intestinal lining is like a skin. We want to make sure that the food and the microbes in our gut don’t get inside our bodies. So just like our skin, we want to make sure that intestinal lining works well in keeping out the antigen, but letting the nutrients and the desired compounds to go through.

[This very current September 2, 2025, 50-minute video, covers much of the same ground as her Stanford talk.]

Dalia Perelman: Live and active confusion—challenges in translating fermented food science to the marketplace

Do you want to talk about bacillus? This is a very hardy strain. You know, spore-forming, can withstand all the industrial processes. And they still can call it ‘live and active’. So ‘ you see  kombucha and it says ‘live active cultures with bacillus’. So consumers think, okay, this is a good kombucha. And maybe it is. I agree it is a fermented product, but it’s probably pasteurized post-fermentation. And then they added the bacillus to be able to still say ‘live and active’. Is that good or bad? It is. And the other kombucha doesn’t have it. The one that doesn’t have the bacillus is probably a really good one. So the marketplace has responded to the demand by having many products. But it did add to the confusion. We’re already confused enough, and they added more confusion. So this is a tough place to navigate.

Sean Spencer: Fermented food metabolites promote anti-inflationary microbiome-immune crosstalk

The Prolongation of Life: Optimistic Studies is a classic 1907 book by Nobel laureate Élie Metchnikoff. He was obsessed with many things in his life, but one of them was that many people around the world consume sour milk, and he thought this was an excellent testimony to its usefulness. He was particularly interested in the Bulgarian kefir consumption, and subsequently isolated L. bulgaricus from fermented milk from Bulgaria. Because of this, he launched the concept of consuming purified microbes, now known as probiotics.

This is currently in the Smithsonian in the U.S.  and is, to my knowledge, the first purified probiotic sold on the streets of Paris called Le Ferment in 1910. The package insert says they’re composed of pure cultures of lactic bacilli that have been prepared according to instructions of Professor Meshcock.

[The full text is available online for free download via Project Gutenberg.]

“From time immemorial human beings have absorbed quantities of lactic microbes by consuming in the uncooked condition substances such as soured milk, kephir, sauerkraut, or salted cucumbers which have undergone lactic fermentation. By these means they have unknowingly lessened the evil consequences of intestinal putrefaction.” – The Prolongation of Life, p.171.

Vayu Hill-Mani: From lab to table: harnessing filamentous fungi for a sustainable food system

Our vision is to move from this linear paradigm of crops into food generating waste to a circular one, where the byproducts are moved back into the food system, not as energy you’re burning in a plant or something, but actually as human food. So how do we convert waste into food? That’s the mission and goal of our lab right now. And all we have to do is look at nature. This is where fungi come in. Filamentous fungi, like mulch and mushrooms, are nature’s degraders. Their job is to break down waste, stuff that we consider useless, like leaf litter or wood or other kinds of things, and break it down into molecules that support healthy ecosystems. Fungi have a superpower. They grow on waste. And it turns out that a single fungus called Neurospora intermedia is the main organism that converts soy milk waste into anchan and turns waste into food. It eats cellulose, things that we cannot digest as humans. It eats it and helps it grow. It produces vitamins, flavors, and so forth.

Doug McMaster: The golden gateway to zero waste

Where industrialism breathes, nature dies. Through industrial agriculture destroying the microbiome of the soil, antibiotics destroying the microbiome of our guts, an industrial process, dead food, was not of nature. And so understanding that we need to design back to nature was a kind of a sign to go back and find natural systems.

Note

The transcripts were generated by TurboScribe from my personal recordings of the conference. The quotes have been edited for readability. Additional references are indicated in […]