yogurt

Scientists revive old Bulgarian recipe to make yogurt with ants

Fermenting milk to make yogurt, cheeses, or kefir is an ancient practice, and different cultures have their own traditional methods, often preserved in oral histories. The forests of Bulgaria and Turkey have an abundance of red wood ants, for instance, so a time-honored Bulgarian yogurt-making practice involves dropping a few live ants (or crushed-up ant eggs) into the milk to jump-start fermentation. Scientists have now figured out why the ants are so effective in making edible yogurt, according to a paper published in the journal iScience. The authors even collaborated with chefs to create modern recipes using ant yogurt.

“Today’s yogurts are typically made with just two bacterial strains,” said co-author Leonie Jahn from the Technical University of Denmark. “If you look at traditional yogurt, you have much bigger biodiversity, varying based on location, households, and season. That brings more flavors, textures, and personality.”

If you want to study traditional culinary methods, it helps to go where those traditions emerged, since the locals likely still retain memories and oral histories of said culinary methods—in this case, Nova Mahala, Bulgaria, where co-author Sevgi Mutlu Sirakova’s family still lives. To recreate the region’s ant yogurt, the team followed instructions from Sirakova’s uncle. They used fresh raw cow milk, warmed until scalding, “such that it could ‘bite your pinkie finger,'” per the authors. Four live red wood ants were then collected from a local colony and added to the milk.

The authors secured the milk with cheesecloth and wrapped the glass container in fabric for insulation before burying it inside the ant colony, covering the container completely with the mound material. “The nest itself is known to produce heat and thus act as an incubator for yogurt fermentation,” they wrote. They retrieved the container 26 hours later to taste it and check the pH, stirring it to observe the coagulation. The milk had definitely begun to thicken and sour, producing the early stage of yogurt. Tasters described it as “slightly tangy, herbaceous,” with notes of “grass-fed fat.”

Popular gut probiotic completely craps out in randomized controlled trial

activia, B. lactis, Bifidobacterium animalis subsp. lactis, constipation, digestive disorder, digestive system, functional constipation, health, probiotic, Science, yogurt / Kelly Newman / October 3, 2024

Any striking marketing claims in companies’ ads about the gut benefits of a popular probiotic may be full of, well, the same thing that has their target audience backed up.

In a randomized controlled trial, the probiotic Bifidobacterium animalis subsp. lactis—used in many probiotic products, including Dannon’s Activia yogurts—did nothing to improve bowel health in people with constipation, according to data from a randomized triple-blind placebo-controlled clinical trial published Wednesday in JAMA Network Open.

The study adds to a mixed and mostly unconvincing body of scientific literature on the bowel benefits of the bacterium, substrains of which are sometimes sold with faux scientific-sounding names in products. Dannon, for instance, previously marketed its substrain, DN-173 010, as “Bifidus regularis.”

Digested data

For the new study, researchers in China recruited 228 middle-aged adults, 85 percent of whom were women. The participants, all from Shanghai, were considered healthy based on medical testing and records, except for reporting functional constipation. This is a condition defined by having two or more signs of difficulty evacuating the bowels, such as frequent straining and having rock-like stool. For the study, the researchers included the additional criterion that participants have three or fewer complete, spontaneous bowel movements (CSBMs) per week.

The participants were randomized to take either a placebo (117 participants) or the probiotic (112 participants) every day for eight weeks. Both groups got packets of sweetened powder that participants added to a glass of water taken before breakfast each morning. In addition to a sweetener, the daily probiotic packets contained freeze-dried Bifidobacterium animalis subsp. lactis substrain HN019, which is used in some commercial probiotic products. The first dose had a concentration of 7 × 10⁹ colony-forming units (CFUs), then participants shifted to a daily dose of 4.69 × 10⁹ CFUs. Many probiotic products have doses of B. lactis in ranges from 1 × 10⁹ to 17 × 10⁹.