Scientists used ants to make yogurt. Diners in a Michelin-starred restaurant ate it

Ice cream, mascarpone and milk-washed cocktails may sound like simple pleasures — but the ones served at a two-Michelin-starred restaurant in Denmark contained a little extra something: ants.

Alchemist in Copenhagen, currently ranked No. 5 on The World’s 50 Best Restaurants list, describes itself as “part science lab” and has a thing for experimenting with food.

The restaurant’s ant-ics began when staff noticed that milk started to curdle when a chef left it in a fridge with an ant inside. This led to experiments involving anthropologists, culinary innovators and food scientists, food innovation researcher Nabila Rodríguez Valerón told CNN. She is head of flavor fermentation at Danish food tech company Summ Ingredients (formerly Nutrumami), a former food scientist at Alchemist and coauthor of a study describing the results that was published Friday in the journal iScience.

The fermentation of milk into cheese and yogurt dates back about 9,000 years to Anatolia, part of modern-day Turkey, according to the study.

Microbes from natural plants like pine cones and nettles added to the milk would start the fermentation process that turns milk into thick, acidic yogurt.

However, after microbiologists successfully made yogurt in a lab in the early 1900s, there was a shift from traditional yogurt to a simplified, industrialized version, which only contains two species of lactic acid bacteria, the researchers said.

This makes the yogurt “safe for the high scale that we have to make foods, but the thing about traditional yogurt is they might have some of these two species, but they have many others, and that adds to the complexity,” lead study author and biologist Veronica Marie Sinotte, an assistant professor at the University of Copenhagen, told CNN.

The researchers therefore decided to explore a traditional spring practice in Bulgaria of making yogurt using a red wood ant colony, believing that the ants and their microbes could contribute the enzymes and acids needed to kick off fermentation.

The study team visited a village in Bulgaria that was the ancestral home of study coauthor and evolutionary biologist Sandra B. Andersen, associate professor of hologenomics at the University of Copenhagen.

The community there “only had living memories of” the practice, but they helped the researchers try to make the yogurt several times, Sinotte said.

The team then made a final ant yogurt by milking a cow, warming the milk, pouring the milk into a jar, adding four live ants, covering the jar with a cheesecloth and burying it inside the ant colony, she added.

While “it was early May, so it was a bit chilly at that time and maybe the fermentation was a little bit slower than normal,” the next day, they found that the milk “was an early stage of yogurt. It had a slight tangy flavor” and had started to thicken, Sinotte said.

Tangy, lemony and silky

To test how ant yogurt could be used in cooking, the research and development team at Alchemist then created three dishes, using live, frozen and dehydrated ants.

The first was an “ant-wich” ice cream made using sheep yogurt that had been fermented using live ants. The ice cream was sandwiched between ant-shaped cookies with an ant-infused gel, according to the study, which noted that the “ants provided a distinct, pungent acidity that contrasts with the fat of the milk.”

The second was a goat milk “mascarpone,” with dehydrated ants used to start the milk fermentation. While the texture was similar to that of a regular mascarpone, “the flavor was pungent and aromatic, such as a mature pecorino cheese,” the researchers said.

The final creation was a milk-washed cocktail. Normally, acid from citrus is used to curdle the milk, before the solids are removed to leave a rich drink. Here, however, dehydrated ants were used to induce curdling. The cocktail also contained an apricot liqueur and brandy, according to the study.

“The milk-washed cocktail, wow, that was phenomenal. Absolutely incredible, because you got the acidity of the ants, which is lemony but a little bit slightly more complex than lemony,” said Sinotte, adding that the drink had an “amazing silky” flavor.

“One microorganism produces some specific aroma compound, but when you use many different ones, like for example, all the microorganisms that ants carry with them, the complexity is like sourdough or, for example, miso or soy sauce,” said study coauthor Valerón.

A spokesperson for Alchemist told CNN that the “ant-wich” went on to be served in the restaurant for about a year and was “very appreciated” by diners.

The researchers also did further experiments in the sterile conditions of a lab in Denmark with ants that were the sister species of the ones used in Bulgaria.

In the lab, the team crushed the ants to release more enzymes and microbes, and left the milk for eight hours in warmer conditions than they did in Bulgaria, Sinotte said.

The researchers found that live ants worked much better than dehydrated and frozen ants as a starter for fermentation.

The live ants consistently introduced lactic acid, as well as acetic acid, to the milk, and the live ant yogurt contained several species of lactic acid bacteria, according to the study.

In the yogurts made with frozen and dehydrated ants, there was not much lactic acid bacteria, but they did contain several species of bacteria known as Bacillaceae, one of which was a food contaminant, the researchers noted. They added that dehydrated and frozen ants and their yogurts are “undesirable” for food fermentation.

“It’s one of the most delightful studies I’ve read in a while,” Changqi Liu, a professor in the School of Exercise and Nutritional Sciences at San Diego State University, told CNN. He was not involved in the study.

“This shows that insects are more than just a novel source of nutrients. They can play a role in transforming and diversifying the way we make food,” he said.

“It also reminds us that traditional practices can reveal new scientific insights when examined closely,” Liu continued, adding: “Personally, I’d love to try ant yogurt as long as it comes without parasites and pathogens.”

Don’t try this at home

Despite ant dishes being served at Alchemist, the researchers caution against people making ant yogurt at home, unless they already do so in their culture or are skilled food microbiologists, due to “food safety concerns.”

The European red wood ants used in the study can carry a parasite, Dicrocoelium dendriticum, that can be “dangerous” to humans, the researchers said.

When mixing the live ants with milk, the researchers strained the milk through a filter that allowed bacteria and yeast to move through, but which removed any parasites.

While freezing can also kill the parasite, freezing and then warming the milk for a long time for fermentation could cause foodborne pathogens to arise, according to the study.

“It’s a very valid concern,” food chemist Andrea Liceaga told CNN.

“But, as they mentioned in the study as well, there’s other ways that we can mitigate those safety hazards,” said Liceaga, a professor of food science at Purdue University in West Lafayette, Indiana, who was not involved in the study.

The scientists noted that taking their research forward is not simply a case of working out how to scale up ant yogurt production. European red wood ants are listed as near-threatened on the International Union for Conservation of Nature Red List of Threatened Species.

“It’s not really feasible to go harvest a bunch of ants and do this, actually,” Sinotte said. “They’re important and part of the ecosystems. So, what we could think is maybe these ants have actually exciting bacteria in them and we could go collect some of that bacteria and see how it works for fermentation for new types of food.”

Traditional fermentation “makes a lot of sense,” said Valerón, because using a “huge” community of microorganisms “is much healthier than eating just one strain of bacteria” and is “good for the human gut.”

“So I would love to see those kind of fermentation in the future, and I think it’s the way that food systems or (the) food industry should go, with the diversity of different microorganisms,” she added.

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