Yogurt is usually thought of as a simple food made with just two types of bacteria.
But a team of researchers has rediscovered a nearly forgotten method from the Balkans and Turkey that uses ants to ferment milk into yogurt.
Their findings, published in iScience on October 3, show how the natural acids, bacteria, and enzymes found in ants can kickstart fermentation. The work not only revives an old tradition but also shows how food science can be inspired by cultural heritage.
Senior author Leonie Jahn, from the Technical University of Denmark, explains that traditional yogurts used to be far more diverse. Depending on the household, season, and location, the mix of microbes varied greatly.
This diversity gave yogurt richer flavors, more textures, and a stronger sense of identity.
The custom of using red wood ants (Formica species) to make yogurt was once common in rural parts of the Balkans and Turkey. To explore this tradition, the research team traveled to anthropologist Sevgi Mutlu Sirakova’s family village in Bulgaria.
Locals there recalled how ants were used to start yogurt.
Following their instructions, the scientists dropped four live ants into a jar of warm milk and then buried the jar inside an ant mound overnight. By the next day, the milk had thickened and soured, taking on the taste of early-stage yogurt.
The team described the flavor as tangy, slightly herbal, and reminiscent of grass-fed dairy. Back in the lab in Denmark, they studied the process more closely.
They discovered that the ants carry lactic and acetic acid bacteria, similar to those used in bread making and other fermented foods. These bacteria, along with the ant’s own formic acid, helped acidify and thicken the milk.
Enzymes from both the ants and the microbes worked together to break down milk proteins, transforming the liquid into yogurt.
The researchers tested the method with live, frozen, and dehydrated ants. Only live ants were able to provide the right community of microbes to start fermentation. But they also warned that caution is needed: ants can sometimes carry parasites or harmful bacteria, so food safety must be considered before reviving this tradition widely.
To explore modern culinary uses, the team collaborated with chefs at Alchemist, a Michelin two-star restaurant in Copenhagen.
The chefs experimented with ant yogurt, creating dishes such as yogurt ice cream sandwiches shaped like ants, mascarpone-style cheese with a sharp tang, and even cocktails clarified with ant yogurt.
For the researchers, the project is about more than unusual recipes. “These traditions may sound strange, but they have real meaning and purpose,” said Jahn.
Lead author Veronica Sinotte added that preserving community knowledge is important: “When a grandmother shares a recipe that seems odd, it’s worth listening. These practices are part of our biocultural heritage and can inspire creative new foods.”
By bringing ants back into yogurt-making, the study shows how old traditions can spark new possibilities at the dinner table.
