Scientists Make Yogurt Using Ancient Ant

In a remarkable fusion of modern food science and ancient folklore, a team of European researchers has successfully revived a nearly forgotten yogurt-making technique from the Balkan Peninsula that uses live ants as a fermentation starter. The study, published in the journal iScience, decodes the complex biological processes behind a tradition that lingered in the oral history of communities in Bulgaria and Turkey. By collaborating with villagers in Bulgaria who retained knowledge of the practice, scientists from the Technical University of Denmark and the University of Copenhagen were able to recreate the yogurt, revealing how the insects introduce a unique combination of bacteria, acids, and enzymes to transform milk. The project was initiated after anthropologist Sevgi Mutlu Sirakova of Ludwig Maximilian University grew up hearing stories from her family in the Bulgarian village of Nova Mahala about the practice.

The research team traveled to Nova Mahala, where community members guided them in the traditional method. Following local instructions, they collected red wood ants (Formica rufa) from a nearby forest, added four live insects to a jar of warm milk, and buried the container in an ant mound to incubate overnight. The result was a thickened, coagulated milk product with a tangy and herbaceous flavor. Subsequent lab analysis in Denmark revealed the science behind the transformation. The ants act as a "holobiont," a complete ecological unit of the insect and its associated microbes, which together kickstart the fermentation. They introduce beneficial lactic and acetic acid bacteria, some of which are also found in sourdough starters, along with formic acid from their defensive secretions, which helps acidify the milk. Furthermore, enzymes from both the ants and their microbes break down milk proteins to create a distinct texture, even at a lower acidity than conventional yogurt.

This rediscovery does more than just validate what might have been dismissed as a myth; it highlights the vast microbial biodiversity present in traditional foods, which has largely been lost in modern industrial production. "Today's yogurts are typically made with just two bacterial strains," said Leonie Jahn, a microbiologist at the Technical University of Denmark and a co-author of the study. "If you look at traditional yogurt, you have a much bigger biodiversity, varying based on location, households, and season. That brings more flavors, textures, and personality.” The findings not only preserve a piece of culinary heritage but also open new avenues for food innovation, with Michelin-star chefs already experimenting with the "ant yogurt" to create novel dishes. However, the researchers caution against attempting the recipe at home, as wild ants can carry harmful pathogens, and further work is needed before it could be considered for wider food production.

• Historical and Cultural Context: The practice of using ants to ferment milk was once a known technique in parts of the Balkan Peninsula and Turkey, passed down through oral tradition. In places like the Bulgarian village of Nova Mahala, elders retained the memory of using red wood ants when traditional yogurt starters were unavailable. This research project, rooted in ethnographic work, gives scientific legitimacy to such traditional ecological knowledge, documenting and preserving cultural foodways that are at risk of disappearing with the rise of industrial food systems.
• Key Stakeholders and Collaboration: The project was a multidisciplinary effort involving microbiologist Leonie Jahn from the Technical University of Denmark, microecologist Veronica M. Sinotte from the University of Copenhagen, and anthropologist Sevgi Mutlu Sirakova from LMU Munich. Crucially, the research depended on the collaboration with community members in Sirakova's family village in Bulgaria, whose instructions on which ants to use and how to perform the fermentation were vital to the experiment's success.
• The Scientific Methodology in Practice: Following the guidance of villagers, the researchers collected live red wood ants (*Formica rufa*) from a colony near Nova Mahala. They placed four live ants into a jar of warm raw milk, covered it with cheesecloth, and buried it within an active ant mound for approximately 26 hours to incubate. The warmth and microenvironment of the mound facilitated the fermentation. By the next day, the milk had visibly coagulated and its pH had dropped, signaling the formation of an early-stage yogurt which the team then taste-tested.
• A Symphony of Bacteria, Acids, and Enzymes: The study revealed a three-part mechanism. First, the ants carry and introduce lactic and acetic acid bacteria, such as Fructilactobacillus sanfranciscensis, which begin to ferment the milk's sugars. Second, the ants secrete formic acid as a defense mechanism, which further acidifies the milk and creates an ideal environment for these microbes. Third, proteolytic enzymes (proteases) from both the ants and their bacteria break down casein, the main protein in milk, causing it to coagulate and form the yogurt's unique texture.
• A Unique Flavor and Chemical Profile: The resulting yogurt was described by the research team as having a "slight tangy taste with mild herbaceousness and pronounced flavors of grass-fed fat." One of the most intriguing scientific findings was that the ant yogurt firms up at a pH of around 5.0, which is less acidic than conventional yogurt (typically pH 4.6). This suggests that the enzymatic breakdown of milk proteins by the ant holobiont plays a more significant role in creating the texture than acidification alone.
• Implications for Modern Gastronomy: The novel flavor profile and unique properties of ant yogurt have already captured the attention of the culinary world. The research team collaborated with Michelin-star chefs to explore its potential. This led to the creation of several innovative dishes, including a pungent mascarpone-like cheese, a milk-washed cocktail, and an ice cream sandwich playfully dubbed the "ant-wich," demonstrating a direct path from scientific rediscovery to high-end culinary application.
• Challenging Industrial Food Production: The research underscores the significant loss of microbial diversity in modern food production. While most commercial yogurts rely on just two bacterial strains (*Lactobacillus delbrueckii subsp. bulgaricus* and *Streptococcus thermophilus*), traditional methods like this one utilize a complex consortium of microbes that contribute to more nuanced flavors and textures. This study highlights how forgotten practices could inspire new approaches to food fermentation and sustainability.
• Future Developments and Important Caveats: While the study is a success, the authors caution that significant hurdles remain before ant yogurt could become a mainstream product. The use of wild insects in food carries the risk of introducing harmful pathogens, and the process would require rigorous safety testing and regulatory approval for commercial use. The primary value of the research is in demonstrating the scientific basis of a traditional practice and uncovering the potential of insect microbiomes for future food applications.