Ants are the secret ingredient to this tasty yogurt
The insects and their microbes acidify and thicken milk into a creamy, tangy treat
This traditional method of making yogurt begins with four ants and a jar of warmed cow’s milk. The technique was once popular in Bulgaria and Turkey. The ants and their bacteria acidify and thicken the milk into yogurt, a new study shows.
David Zilber
In parts of Eurasia, the key to a tangy yogurt treat scurries along the forest floor. The secret ingredient is ants!
A once-popular yogurt-making technique uses ants and their microbes as a bacterial starter for this process. Those bacteria are used to kick-start the fermentation process that makes yogurt so thick and tangy.
The traditional recipe requires live ants — not frozen or dehydrated ones. Now, scientists have identified the exact microbes the ants have that make this creamy treat so tasty. They shared the details in the October 17 issue of iScience.
Yogurt-making dates to around 7,000 years ago. The process starts with warm milk. Then people add safe, healthy bacteria to acidify and thicken the liquid. They keep the mixture warm for several hours, giving it time to ferment.
The bacteria used in making yogurt can come from many sources.
Traditional recipes use a variety of bacterial species. In parts of Turkey, people have started yogurt cultures with pinecones or chamomile flowers. But today, modern technology requires just a few acid-producing microbes.
Factories need to make a lot of yogurt quickly. Their controlled process ensures that the food is safe to eat and easy to sell.
“We reach a point that is the perfect middle ground for everyone in the flavor profile,” says Veronica Sinotte. She’s a microbial ecologist at the University of Copenhagen. That’s in Denmark. The taste of homemade yogurt, in contrast, can vary widely. It will depend on who made it and how.
In parts of Bulgaria, for instance, where some people make yogurt from scratch, neighbors will know each other’s recipes well. “If they were given a lineup of yogurts, they could tell us which house the yogurt came from,” Sinotte says.
Time for ferm-ant-ation
Anthropologist Sevgi Mutlu Sirakova works at Ludwig-Maximilians-University Munich. That’s in Germany. Her ancestors come from a village in Bulgaria. Around there, it was once common to make yogurt with the help of red wood ants (Formica rufa and F. polyctena).
Sinotte, Sirakova and their rest of their research team traveled to Sirakova’s family village. There, they put the insect-based practice to the test.
Ants away!
To start the yogurt-making test, researchers put four live ants in a jar of milk. They bury it in an ant mound and leave it to ferment overnight. The ant colony produces heat to keep the bacteria warm enough to grow.
The team placed four live ants into a jar of warmed raw cow’s milk. They then buried the jar in an ant mound. The nest kept the mixture warm so that it would ferment overnight. The next day, the now-acidic milk had begun the early stages of becoming yogurt. It developed a tangy and herb-like taste.
Molecular analyses showed that F. polyctena ants carry bacteria that produce lactic acid and acetic acid, which thicken milk. One of these microbes was Fructilactobacillus sanfranciscensis (Frook-tih-bah-SIL-us San-fran-sih-SEN-sis). This species can also be found in sourdough bread.
The ants add formic acid to the mix too. In nature, ants use this chemical to defend against predators. Enzymes supplied by both ants, along with those bacteria, can digest the milk. This breaks it down and makes creamy yogurt.
Frozen or dehydrated ants carry microbes that don’t ferment milk as well as living ants do, the team found. However, live ants can be infected with a hitchhiking parasite. In rare cases, that hitchhiker can harm the liver or gastrointestinal tract, Sinotte says. As a result, she cautions: “I don’t suggest your average person go make [yogurt this way] at home.”
