Fermenting “Cowcohol”

Oregon-based TMK Creamery is using the leftover whey byproduct from their cheese and fermenting it into vodka. They call it “cowcohol” and the flavor has a carmel-like sweetness with a smooth finish. Owner Todd Koch learned about the method from Dr. Paul Hughes, assistant professor of Distilled Spirits at Oregon State University. Hughes began experimenting with fermenting whey into a spirits base and has now helped more than a dozen creameries all over the U.S. ferment their whey into alcohol. 
Fermenting upcycles the whey while bringing some attention to the animals, Koch said. Artisanal creameries typically have to pay thousands of dollars to dispose of whey in landfills. 

From Atlas Obscura: Whey fermentation offers a brave, new world for small creameries, both in decreasing their environmental footprint and ensuring financial security in an age of mass conglomeration. For Koch, a life-long, self-proclaimed “cow person,” the possibilities of bovine booze are a relief to him and his beloved herd. “Going through college, I was like ‘Man, if I could just figure out how to get cows to make alcohol, we’d be set,’” he says. “So I guess we’re one step closer here.”

Read more (Atlas Obscura)

Americans are hearing the term “microbiome” a lot lately. It’s become a common phrase in health food marketing. But the microbiome is still uncharted territory in science.

Dr. Shilpa Ravella, a gastroenterologist and professor of medicine at Columbia University Medical Center, says a large army of trillions of bacteria lives on or in us, and we can alter that bacteria by fueling it with the right (or wrong) foods.

“There are also ways of preparing food that can actually introduce good bacteria, also known as probiotics, into your gut. Fermented foods are teeming with helpful probiotic bacteria, like lactobacillus and bifidobacteria,” Ravella says.

Fermented food and drink are critical to caring for gut bacteria. Because fermented products are minimally processed and provide nutrient-rich variety to diets, she adds.

But that doesn’t mean all fermented products are created equally. Yogurt is a beneficial food, for example, but some brands add too much sugar and not enough beneficial bacteria that the yogurt may not actually help.

Ravella shared her insight in a TedED talk. As the director of Columbia’s Adult Small Bowel Program, she works with patients plagued by gut issues.
“We don’t yet have the blueprint for exactly which good bacteria a robust gut needs, but we do know it’s important for a healthy microbiome to have a variety of bacterial species,” she adds. “Maintaining a good balanced relationship with them is to our advantage.”

Gut bacteria breaks down food the body can’t digest, produces important nutrients, regulates the immune system and protects our bodies from harmful germs.

Though multiple factors affect our microbiome – the environment, medications and even whether or not we were birthed vaginally or through a C-section – the food we eat is one of the most powerful allies for the microbiome.

“Diet is emerging as one of the leading influences on the health of our guts,” Ravella adds. “While we can’t control all these factors, we can manipulate the balance of our microbes by paying attention to what we eat.”

In addition to fermented food and drink, fiber is also key. Dietary fiber in foods like fruit, vegetables, nuts, legumes and whole grain are scientifically proven to colonize the gut.

“While we’re only beginning to understand the vast wilderness inside our guts, we already have a glimpse of how crucial our microbiomes are for digestive health,” Ravella says. “We have the power to fire up the bacteria in our bellies.”

The new wave of protein is not plant-based — it’s fermented.

“Fermentation is really cultivating microbes,” says Thomas Jonas, CEO and co-founder of Sustainable Bioproducts. “And it’s incredibly efficient. Microbes duplicate very fast. So when you think about the double time for a cow or a pig, you’re talking about years. When you talk about microbes, you’re talking about hours. … This is nature’s technology. Nature is really the No. 1 biotech engineer in the world.”

The current agriculture system is incredibly inefficient. Livestock continues to be the world’s largest user of land resources. Pasture land consumes 80% of total agricultural land. Fermented organisms are emerging as new sources of proteins and ingredients. 

Leaders in the biotech industry shared how science is looking beyond plants to create food at a panel sponsored by The Good Food Institute.

Is Microbe Fermentation the New Era of Farming?

Sustainable Bioproducts creates a 50% protein based food ingredient from a microbe cultivated in the volcanic springs at Yellowstone National Park. Jonas explains that these fungal strains, called extremophiles, naturally produce a complete protein when grown in a controlled environment. Sustainable Bioproducts will soon move to a 36,000-square foot facility in Chicago’s former meatpacking district for production. The facility will take up just 0.7 acres. Compare the amount of food Sustainable Bioproducts produces to the equivalent of cow meat and 7,000 acres of grazing land would be needed for the cows.

“It’s the next generation of very efficient farming. I think what we want to get through farming are the nutrients that we need for our food. And microbes can do this tremendously efficiently,” Jonas said. 

By fermenting proteins in bioreactors versus deriving the protein from plants or raising it and slaughtering it on a feedlot, food scientists can do a lot with the health profiles.

Michele Fite, chief commercial officer for Motif FoodWorks, said they work with microbes to adjust sensory attributes, like taste, smell, flavor and texture. “We can help so we don’t have to compromise taste or nutrition when consumers are looking to access plant based foods,” she said.

Adds Anja Schwenzfeier, business development manager for Novozymes: “You want to produce specific proteins that might already exist, but you want to do that more efficiently and more sustainably. You deal with molecules you’re already familiar with.” 

“It’s not so much about creating a completely new protein. Right now we’re looking into how we can improve ingredients we already work with through fermentation.”

Fermentation as a Marketing Advantage

Panel moderator Jeff Bercovici, a writer for the Los Angeles Times, asked how biotech companies are meeting consumers in the development of fermented meat alternatives.

“(There is an) evolution of consumer attitude towards their food, which in some ways are really driving them very quickly to embrace meat alternatives, but in some ways there are some counter currents in terms of people wanting to eat whole foods, natural foods, foods with shorter ingredient lists,” Bercovici said.

The panel noted fermentation has long been a stable in the history of food, from beer to yogurt to cheese. As fermentation is making a comeback, it’s a “marketing advantage,” Bercovici notes, “now it’s a net positive, it generates consumer excitement.”

Fite at Motif FoodWorks said they’ve conducted research on meat alternative users. These consumers are currently buying meat alternatives because they believe it’s healthier than red meat and even chicken. “They want to be in this space,” she said. Consumers voice that meat alternatives are more sustainable, better for the environment, better for animal welfare and equally nutritious.

“They’re open to technology helping to solve that issue for them,” she said. “These consumers are more open to technical solutions than consumers that are a lot older have been in the past…there’s a gateway for these consumers to technical advancements, because they believe it aligns with their values.”

Adds Mark Matlock, senior vice president of food research at Archer Daniels Midland Company: “To me, it’s really refreshing to have some consumers who are embracing technology to this degree, to the extent that they may lead the mainstream their direction.”

Battling Land Use Challenges

As the global population grows, the great challenge to the environment over the next decade will be making more food with less space.

The average American consumes 215 pounds of meat a year. Raising that meat uses 32 million acres of land, and produces 82 million metric tons of greenhouse emissions.

“The real challenge for the planet is not going to be ‘Are we going to have enough oil or carbohydrates?’ it’s ‘Are we going to have enough protein?’” Matlock said. “We create protein the way a cow creates protein. … we have to think: where are our rare resources going to be put?”

A third of the corn crop grown in America feeds livestock.

A Japanese study published in the British Medical Journal found that people eating higher amounts of fermented soy products (like miso and natto) reduce their mortality risk. Participants with the highest intakes of fermented soy had a 10% lower risk, compared with those who had the lowest intakes. For participants who ate a lot of soy products that were not fermented, no significant association was found between intake of soy products and mortality rate.

Read more (British Medical Journal)

Kombucha has its first international holiday. On February 21, kombucha brewers and consumers around the world will celebrate World Kombucha Day.

Kombucha dates back over 2,000 years to 221 B.C. The fermented tea is one of the fastest growing beverages in the world. Kombucha is estimated to reach $3.5 billion in international sales by 2025, with one third of that  in U.S. sales. Hannah Crum, founder and president of Kombucha Brewers International (KBI), a non-profit trade association (and an affiliate of TFA), believes 2020 will be the decade kombucha becomes mainstream.

Educating the public, though, is the key step to making kombucha a recognized wellness drink. KBI began the World Kombucha Day initiative and is encouraging brands to host events, offer free tastings and partner with retails for in-store promotions.

Since KBI started six years ago, Crum has watched the small kombucha labels that joined KBI transform into big brands. She sees the kombucha industry growing not with big kombucha labels but with small craft brands. If consumers in small towns all over the world start purchasing kombucha, local producers will need to drive that growth, Crum adds.

“And it opens the door for all these other fermented products to come in,” Crum adds. “Drinking vinegar, shrubs, water kefir, even sauerkraut and fermented vegetables. Local brands will drive the entire fermented food and drink category.”

Below, a Q&A with Crum on World Kombucha Day and how kombucha can maintain their growth momentum. 

Question: Why a World Kombucha Day?

Hannah Crum: Kombucha’s mythological origins hearken back to 221 BC in China. The Chinese are famous for their quest for longevity with their elixirs. It’s been part of the story of kombucha, this mythological origin. So 221, at least in the American system, translates to February 21st. What better year to launch it than in 2020.

Why World Kombucha Day? To celebrate the culture of kombucha. Obviously drinking a commercial brand is how I first heard about kombucha. It’s how most people first experience kombucha, even though home brewing has been around for a long time. It’s a way for people to raise awareness about kombucha, to be excited about what it is, to honor its Asian roots, and to really help more people know about kombucha.

This is the decade when kombucha becomes a household name. Launching this world kombucha day in 2020, in this decade, is that first step towards building excitement around kombucha. Not just the drink being trendy, because i think it’s going to last longer than a trend. It’s getting more people to wake up to how wonderful this product is. 

We think of kombucha as a gateway. Kombucha isn’t an end point. We don’t stop at kombucha, we start with kombucha. From kombucha, people move to other products in the fermentation association, now it’s sauerkraut and kimchi and kvas and water kefir. I don’t even think we could see this many water kefir brands starting to emerge if kombucha didn’t exist. 

Q: Tell me the process of making World Kombucha Day an official “day.”

HC: The process is pretty straight forward and basically just means coming up with the day and promoting it. We have applied to some of the calendars and apparently if you pay enough money, you can even make it onto the National Holiday Calendar.

Q: What are you hoping brands will do to celebrate World Kombucha Day? 

HC: I’m hoping they’ll elevate kombucha into the consciousness. That can be providing education, and education could come in the form of free samples or offering a promo at your favorite store. It’s on a Friday this year — if you happen to be at a farmers market or you happen to have a tap room, why not host an education event. 

Really it’s this opportunity to engage with your community, do this outreach and to help people understand what kombucha is. Because so many people still either haven’t heard the word, they don’t know what it is, they’re afraid of it, they’ve tried it and think its weird, whatever it is, just giving them another touch point, another opportunity to hear about it, another opportunity to try it without having to pay $3-5 per bottle in order to see what it’s like. 

People can add events to our World Kombucha Day calendar based on region. This is free, open to all kombucha producers, not just KBI members. While World Kombucha Day is a KBI initiative, it’s really about the category of kombucha. 

Q: Tell me more about KBI origins. Why did you create KBI ?

HC: It started with our business, Kombucha Kamp, and our mission: changing the world, one gut at a time. 

KBI also comes from looking at our culture which works in symbiosis. We’ve always understood we can’t do this alone, we have to do this in partnership, we have to be in community. Changing the gut one world at a time, knowing we can’t do it alone, and how do most people find out about kombucha? Again it’s through a commercial product.

In 2010, we had that incident where Whole Foods took all the kombucha off of store shelves and it really creates a lot of fear. It’s a trauma point that we’ve continued to have to work through together. That is what inspired us to come together and really make this work.

We know: people don’t really understand what kombucha is. When you don’t know about something, you’re afraid of it. People worry “I’m going to get bad bacteria in my brew and harm myself.” Well, that’s highly unlikely, just like any fermented food. The only reason they still exist today is because they’ve always been so incredibly safe to make and pass around or they would have been on the compost heap of history ages ago.

So knowing that there was a need, we have a unique roll. We’ve already been doing some cross-category marketing. We did a 30-day kombucha challenge, we did a New Years re-evolution, which were all designed to raise awareness about the category.

So I nominated myself to head KBI and Alex (Crum’s husband), God love him, supported me. We started with KKon (KombuchaKon) in 2014, and here we are about to have our 7th annual show, our 5th annual trade show. We’ve grown from 40 members to over 300. We’ve always been international though, which is unique. We’ve always had people from around the world participating with us.

Q: Is the U.S. leading the growing kombucha popularity?

HC: Yes. America leads the world  because this is where the commercial industry started. GT’s is going to celebrate his 25th anniversary this year. Kombucha has been a commercially available product for 25 years. Even now its taken this long, right, even in the early years it wasn’t around until 2010 when it started to pick up steam and we started to see more brands proliferate. Now here in 2020, we’re going to make it a household name.

Just like yogurt wasn’t a household staple, it was something hippies had to make at home on their countertops themselves, then it was turned into a multi-billion dollar industry. And that’s exactly what we see kombucha becoming. What we see isn’t the opportunity for a bunch of processed food companies. Rather its a bunch of small, family-owned businesses that serve local communities with a fresh product. That’s what’s different and unique about all the fermentation businesses.

I love Farmhouse Cultures — I just bought a bottle of their kraut juice — I look on the back and they’re adding vinegar to it. You can’t keep up when you’re a massive brand and you’re going to have to take shortcuts. To me, yes it tastes good, but its not kraut juice, its vinegar and kraut juice. Unfortunately, that’s just what happens when you go too big with certain things.

People in the 21st Century are looking for viable opportunities with a job that makes you feel good about the work you’re doing and that helps your local communities, and it’s important for these communities to have access to really fresh, nutrient-dense foods. So I always advise people: there’s an opportunity, as long as you’re not afraid of hard work. I advise people its a labor of love, emphasis on the labor. But I also think that if you’re someone who wants to be in your community doing good, this is a great way to do it.

Q: Do you think that’s how the kombucha industry is going to  grow — more small producers than large?

HC: Exactly right. There’s always going to be a certain number of large producers and brands that want to pursue that type of dream, but it’s a huge trade off. Sure you might end up with a bigger paycheck in the end, but you also give up so much of your life and energy in order to make it profitable.

You’re never going to have another GT’s Kombucha. He was first to market. That was a rare opportunity. Were not likely to see an individually or privately owned brand get to that type of level unless they have investment and if you take on an investment, now you are beholden to other people’s ideas about your business.

Look at the beer industry and how things have happened there. New Belgium just sold to a major food corporation from Asia because even economies of scale aren’t sustainable if you don’t continue to have capital infusions. So if you’re looking for a model that will stay sustainable over time, I think it is staying small, having a local footprint, and again that’s better for the planet, better for the community. The reason products need super long shelf lives on them is because it’s being shipped massive distances. If you only have to go to your local place to get kombucha fresh, you don’t have to put so much processing into your products.

Q: Tell me what you’re seeing in the industry now — are craft beer brewers entering the market? Bigger commercial soda brands?

HC: All of these entrants, it’s exciting. What they are seeing are dollar signs and opportunities. Especially as they see their sales slipping. It’s true for craft beer as it is for soda. 

That’s just reflecting how consumers are changing their tastes over time. It’s always healthy to diversify. The reality is what we would love — Coca-Cola started as a health drink, selling in pharmacies, with actual essences and things that were good for you. And now it’s turned into a fake version of a real thing, full of fake ingredients. How wonderful would it be for us as an industry, for us to bring them back to the good side. Don’t poison people with your cheap products and aspartame and things that are known to be toxins. Let’s try to make this something that brings about positive change to everybody. 

We love beer too! I think what we’ll also start to see is the benefits of unfiltered beer. I personally believe that pasteurization and these processing steps that remove the yeast or all of the living nutrients from beer basically creates products that don’t deliver on the nutritional promise that was guaranteed for our ancestors.

We crave bubbles because our ancestors understood that meant that nutrients were present in a living form. And so many people have come to find they can’t tolerate carbonated water — well that’s carbonic acid, it’s not natural organic acids, it’s not all of the yeast and nutrients present in yeast. 

The conflict is always these are tough products to control. That’s again where the model of having several small producers is actually better.

Q: What are some of the greatest myths consumers believe about kombucha? How can brands debunk the myths?

HC: In the headlines, we get the two polarizing viewpoints — kombucha is the miracle elixir that will save your life and kombucha is snake oil that is dangerous. The reality is the truth is always somewhere in the middle. This is not a beverage for everybody. That’s because we have so many people dealing with a healing crisis. However, there is a ferment for everyone. So either its a miracle cure — or it will kill you. Both of those are the greatest myths. 

Will you feel a benefit from drinking kombucha? Absolutely. We have a research study we presented last year showing how kombucha impacts inflammation and stress markers. They’ve taken that study to the next step, which we’ll be hearing those results at KKon this year.

People have provided anecdotal information for how kombucha has helped them with a wide range of inclement for hundreds, thousands of years, right. And so often science wants to ignore that information. But truly that’s the jumping off point for studying something, for understanding something. It is because of the anecdotal information.

Science is a method of inquiry. The phenomenon already exists. We just don’t necessarily know what’s driving it until we engage in scientific inquiry. So this idea that science is settled, that we already know everything, is ridiculous. It’s human hubris to think that. What I think is exciting is in this 21st Century, we continue to do the research and validate the anecdotal claims, and again not everything is for everybody. Some people are allergic to shrimp, strawberries, you name it, there are people who can be allergic to anything and all that says is we’re diverse and not everything is for everybody and that’s OK. Honestly, I think what’s exciting about our industry is you try one kombucha and don’t like it — try another. It’s going to taste totally different. It’s not a miracle, but it’s not going to kill you. It’s not for everyone, but it helps a lot of people. And that’s what World Kombucha Day tries to do — to introduce you to kombucha and see where you land on that spectrum. 

Q: What is driving kombucha’s popularity in the past few years?

HC: Microbiome. The rise of autoimmune disease and metabolic disease. People are sick of being sick and start to turn to food to get better because they’ve heard you can get better with certain types of food or by changing their diet. And while they are not getting that advice from their doctors, unless they’re seeing a naturopath or something like that, I think people out of desperation are turning to their diet because they’re just so uncomfortable with where they’re at healthwise. That to me is truly what’s fueling the fueling popularity of this product. So many people consume it, and they say they “Just feel good.” What does that mean, how do you quantify that? Is it just my tummy feels more settled? There’s a whole range of things that could refer to. And I think that’s really what’s driving it.

People are waking up. They realize now they’ve been lied to by packaged foods — I call it poisoned in prepackaging by pretty people. How many sodas is Beyonce drinking to be that shape? You know there’s mythology when they’ve put these packages in people’s hands but that’s not who’s actually drinking this on a regular basis. 

Especially this younger generation is more critical of advertising and more critical of doing what everyone else has done until now. They are starting to recognize “Hey what are all  these weird flavorings and chemicals in my food and water?” and “Hey I thought someone was in charge of and managing this?” and then you find out, no, corporations are actually still allowed to dump toxins into the water supply, we still have lead in Michigan and Flint. This mythology of a government that cares for you is being broken down. For good reason. Unfortunately, the forces that be are trying to maintain a status quo because they make money off people being sick for so long. But that really is that change — I’m not saying kombucha will cure everything. Buts it’s a gateway. It’s a gateway to healing your body, getting some kind of relief, and seeing there’s a world of other choices you can make that are going to yield different health benefits.

Q: The soda industry is rapidly declining. Do you think kombucha can capture those consumers?

HC: One thousand percent. Really Who is our competition? It’s not other kombucha brands. Its soda companies, it’s energy drink companies, it’s soda water companies, it’s seltzer water companies, it’s “smart water” that’s water with some electrolytes, it’s Gatorade. It’s all this manufactured, lab-created junk. Supplements will never be as good as the real thing. And kombucha is a real thing — it’s a real fermented beverage. It’s what soda aspires to be.

The same beneficial gut-friendly bacteria prevalent in yogurt is also in some beer, according to new research from scientists at Amsterdam University. Beer brands that ferment twice — once at the brewery, then a second fermentation in the beer bottle — are rich in probiotic yeast. This creates a sharp, dry taste in the beer that is “bursting with probiotic microbes.” Scientists found the brands using in-bottle fermentation use a different strain of yeast than traditional brewer’s yeast. Pasteurized beer and modern beer production processes have no probiotics. Their findings are supported by researchers from the University of Nebraska, who also found some beers contain a high amount of good probiotics. Professor Eric Classeen, a gut bacteria expert from Amsterdam University, said “You are getting a stronger beer that is very, very healthy. … In high concentrations, alcohol is bad for the gut but if you drink just one of these beers every day it would be very good for you.”

Read more (The Telegraph)

“Science is here to explain why fermenting vegetables is not only perfectly safe but also surprisingly easy and rewarding. Spoiler: Microbes do most of the work.

In our hyper-Pasteurian, expiration date-driven era, it might be difficult to relinquish control over our food to these mysterious forces. But a small measure of understanding yields rich rewards: crisp classic sauerkraut, warmly tart beets, bright preserved lemons and just about anything else you can dream up.” Katherine Harmon Courage writes in her article for the Washington Post “Eat Voraciously” section that fermentation adds a depth to fruits and vegetables. Harmon Courage, author of the book Cultured: How Ancient Foods Can Feed Our Microbiome

Read more (Washington Post)

How Alcoholic is Kombucha?

Researchers are studying kombucha to determine whether kombucha brands are unintentionally selling the fermented tea with a high alcohol content. The study, by the British Columbia Center for Disease Control, is testing hundreds of kombucha samples sold at grocery stores and farmers markets for ethanol levels. The fermentation process makes all alcohol slightly alcoholic, but in the U.S. the drink has to be sold below 0.5% to be sold as a non-alcoholic beverage. In Canada the amount is higher, at 1.1%. Researchers are looking at how different control factors affect kombucha’s alcohol content, like how cold refrigeration temperature, where it’s stored in the fridge, how it’s made and type of tea and flavors used.

Read more (CTV News)

For the third year in a row, fermented foods tops Today’s Dietitian list of the year’s No. 1 superfood. The annual “What’s Trending in Nutrition” survey reveals the hottest food and nutrition trends to look for in 2020.

“The 2020 survey results send a clear and consistent message. Consumers want to live healthier lives,” says Louise Pollock, president of Pollock Communications. “They have access to an incredible amount of health information, and they view food as a way to meet their health and wellness goals. Consumers are taking control of their health in ways they never did before, forcing the food industry to evolve and food companies to innovate in response to consumer demand.” 

Consumers are using fermented products as “powerhouse foods,” foods that boost gut health and reduce inflammation. Some nutrition experts recommend fermented foods should be included in national dietary recommendations. 

In April, Today’s Dietitian published an article “The Facts About Fermented Foods.” In it, Dr. Robert Hutkins, a researcher and professor of food science at the University of Nebraska-Lincoln, shared his expert opinion on fermentation. Hutkins wrote what many in the field consider the most exhaustive textbook on fermentation, “Microbiology and Technology of Fermented Foods.” He explained how fermented foods have a long history in the human diet. 

“Indeed, during much of human civilization, a major part of the human diet probably consisted of bread, yogurt, olives, sausages, wine, and other fermentation-derived foods,” Hutkins told Today’s Dietitian. “They can be considered perhaps as our first ‘processed foods.’”

Hutkins, who studies the bacteria in fermented foods, said researchers like himself “are a bit surprised fermented foods suddenly have become trendy.” 

“Consumers are now more interested than ever in fermented foods, from ale to yogurt, and all the kimchi and miso in between,” he says. “This interest is presumably driven by all the small/local/craft/artisan manufacturing of fermented foods and beverages, but the health properties these foods are thought to deliver are also a major driving force.”Fermented foods first appeared in the survey of registered dietitian nutritionists (RDNs) in 2017, where it was the 4th most popular superfood.

The full superfoods list includes:

  1. Fermented foods, like yogurt and kefir
  2. Avocado
  3. Seeds
  4. Exotic fruit, like acai, golden berries
  5. Ancient grains
  6. Blueberries
  7. Nuts 
  8. Non-dairy milk
  9. Beets
  10. Green tea

Taming the Wild Cheese Fungus

By: The American Society for Microbiology 

The flavors of fermented foods are heavily shaped by the fungi that grow on them, but the evolutionary origins of those fungi aren’t well understood. Experimental findings published this week in mBio offer microbiologists a new view on how those molds evolve from wild strains into the domesticated ones used in food production. 

In the paper, microbiologists report that wild-type Penicillium molds can evolve quickly so that after a matter of weeks these strains closely resembled their domesticated cousin, Penicillium camemberti, the mold that gives camembert cheese its distinctive flavor. The study shows how a fungus can remodel its metabolism over a short amount of time; it also demonstrates a strategy for probing the evolution of other cultures used in food, said study leader and microbiologist Dr. Benjamin Wolfe, Ph.D., a member of the The Fermentation Association advisory board.

“In fermented foods, there’s a lot of potential for microbes to evolve and change over time,” said Wolfe.

Wolfe’s lab at Tufts University in Medford, Mass., focuses on microbial diversity in fermented foods, but he says the new experiments began with an accidental discovery. His lab had been growing and studying Penicillium commune, a bluish, wild-type fungus well-known for spoiling cheese and other foods. Wolfe likens its smell to a damp basement. 

But over time, researchers noticed changes in some of the lab dishes containing the stinky mold. “Over a very short time, that funky, blue, musty-smelling fungus stopped making toxins,” Wolfe said. The cultures lost their bluish hue and turned white; they smelled like fresh grass and began to look more P. camemberti. “That suggested it could really change quickly in some environments,” he said.

To study that evolution in real-time, Wolfe and his collaborators collected fungal samples from a cheese cave in Vermont that had been colonized by wild strains of Penicillium molds. The researchers grew the molds in lab dishes containing cheese curds. In some dishes, the wild mold was grown alone; in others, it was grown alongside microbes that are known competitors in the fierce world of cheese colonization. 

After one week, Wolfe said, the molds appeared blue-green and fuzzy—virtually unchanged—in all the experimental tests. But over time, in the dishes where the mold grew alone, its appearance changed. Within three or four weeks of serial passage, during which mold populations were transferred to new dishes containing cheese curds, 30-40 percent of the mold samples began to look more like P. camemberti. In some dishes, it grew whiter and smoother; in others, less fuzzy. (In the competitive test cases, the wild mold did not evolve as quickly or noticeably.) 

In follow-up analyses, Wolfe and his team tried to identify genomic mutations that might explain the quick evolution but didn’t find any obvious culprits. “It’s not necessarily just genetic,” Wolfe said. “There’s something about growing in this cheese environment that likely flips an epigenetic switch. We don’t know what triggers it, and we don’t know how stable it is.” 

Researchers suspect that the microbes used in most fermented foods—including cheese, but also beer, wine, sake, and others—were unintentionally domesticated, and that they evolved different flavors and textures in reaction to growing in a food environment. Wolfe says his lab’s study suggests that wild strains could be domesticated intentionally to produce new kinds of artisanal foods. 

Starting with cheese, of course. “The fungi that are used to make American camembert are French,” said Wolfe, “but maybe we can go out and find wild strains, bring them into the lab, and domesticate them. We could have a diverse new approach to making cheese in the United States.” 
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The American Society for Microbiology is the largest single life science society, composed of more than 30,000 scientists and health professionals. ASM’s mission is to promote and advance the microbial sciences.

ASM advances the microbial sciences through conferences, publications, certifications and educational opportunities. It enhances laboratory capacity around the globe through training and resources. It provides a network for scientists in academia, industry and clinical settings. Additionally, ASM promotes a deeper understanding of the microbial sciences to diverse audiences.