Ants, milk and a pinch of culinary history: Researchers have investigated an unusual yoghurt recipe and find it does indeed work and bring extra flavour. But that doesn’t mean you should try it. David Zilber/dpa

Drop four ants into warm milk, wait a while — and voilà, you have yoghurt.

Researchers from the University of Copenhagen and the Technical University of Denmark have taken a closer look at this traditional fermentation method, which originates from Turkey and the Balkans, and published their findings in the journal iScience.

Spoiler: They don’t advise trying it at home.

The researchers travelled to the Bulgarian hometown of their co-author and anthropologist Sevgi Mutlu Sirakova, where her relatives and other locals explained the tradition.

“We dropped four whole ants into a jar of warm milk by the instruction of Sevgi’s uncle and community members,” says lead author Veronica Sinotte of the University of Copenhagen.

According to the researchers, the glass was then placed overnight in an anthill — a warm environment that provides the right conditions for fermentation.

By the next day, the milk had started to thicken and sour. “That’s an early stage of yoghurt, and it tasted that way as well,” Sinotte explained.

Are the ants eaten?

Technically, ants can be consumed, said study leader Leonie Jahn from the Technical University of Denmark. However, traditionally, the ants are not eaten. Instead, the first batch of yoghurt is used to start new yoghurt cultures.

Back in Denmark, the team investigated how the fermentation process works with the help of the ants. According to the researchers, the wood ants (Formica) native to the region carry lactic acid and acetic acid bacteria, which contribute to the milk’s coagulation.

Some of these bacteria are similar to those found in commercial sourdough. The ants also actively contribute to the process. Their natural chemical defence system includes acid, which acidifies the milk and creates a culture where acid-loving microbes can thrive.

The researchers, who tasted the yoghurt during their trip, described it as slightly tangy. Modern commercial yoghurts are typically made with only two bacterial strains, Jahn explained.

‘More** flavours, textures and personality’**

“If you look at traditional yogurt, you have much bigger biodiversity, varying based on location, households, and season. That brings more flavours, textures and personality.” This diversity influences the taste, texture, and uniqueness of the yoghurt.

““I hope people recognize the importance of community and maybe listen a little closer when their grandmother shares a recipe or memory that seems unusual,” said Sinotte. “Learning from these practices and creating space for biocultural heritage in our foodways is important.”

In several experiments, the researchers found that using live ants produced the best results. Frozen or dried ants did not create a suitable bacterial culture for the process.

In any case, the team warns against trying this method at home, since live ants can carry parasites. Unless it is part of your cultural tradition or you have extensive knowledge of food safety, the researchers advise against attempting it.

The interdisciplinary research team didn’t stop at tasting the yoghurt themselves. Chefs from the two-Michelin-starred restaurant Alchemist in Copenhagen created several dishes inspired by the traditional ant yoghurt, giving it a modern twist.

These included a mascarpone-like cheese, a special cocktail and a yoghurt ice cream sandwich dubbed the “ant-wich”.

Ants, milk and a pinch of culinary history: Researchers have investigated an unusual yoghurt recipe and find it does indeed work and bring extra flavour. But that doesn’t mean you should try it. Zacharie Scheurer/dpa

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