Scientists Make Bread Using Yeast From Oetzi the Iceman

Scientists have now added prehistoric baking experiment to Oezti the Iceman's résumé. An Italy-based team reports in Microbiome that they've isolated four hardy yeasts from the 5,300-year-old mummy's intestines, skin, and meltwater—and eventually used one to bake what they say turned into a solid sourdough loaf after months of trial and error, per AFP. The microbes tolerate extreme cold—Oezti's mummy is stored at 21 degrees Fahrenheit—and can even digest the preservative phenol used on the body in the 1990s, a finding researchers say could have major significance for mummy preservation, per Scientific American.

The work recasts Oezti as less of a sealed time capsule and more of a living ecosystem. Genetic analysis indicates the yeasts likely colonized the corpse shortly after death, then persisted as it lay in the Alps' ice for thousands of years, researchers say, though outside experts caution that the samples, taken in 2010 and 2019, may represent relatively recent arrivals. Oezti's gut microbiome also held a bacterial strain now rare in industrialized populations but still seen in some Indigenous communities and in 3,000-year-old Austrian feces, consistent with a fiber-heavy, whole-grain diet, according to the researchers. They note they might use the yeast to brew beer next.