Alpine archaeology yields 5,300-year-old yeast; scientists brew sourdough from Iceman's remains

Researchers have isolated living yeast from the gastrointestinal tract of Oetzi the Iceman, the naturally mummified human remains discovered in the Alps on the Austria-Italy border, CBS News reported this week. The yeast, which has remained viable in the frozen body for more than 5,300 years, was used by scientists to produce a functioning sourdough starter and bake bread. The discovery, confirmed by researchers speaking to AFP, offers an unprecedented window into the microbial life of prehistoric Alpine communities.

Oetzi was discovered in 1991 on the Similaun glacier, near the border between South Tyrol and Austria, at an elevation of roughly 3,200 metres. The body had been preserved by the Alpine cold and ice for millennia, its tissues, organs, and gut contents intact. The yeast discovery represents one of the oldest living microorganisms ever recovered from human remains, and the first time such ancient microbes have been successfully cultured and used to produce food.

The implications for Alpine archaeology are substantial. Oetzi's gut contents have long been studied to understand prehistoric diet and trade patterns. The presence of viable yeast suggests that fermentation—and thus bread-making, beer production, and other fermented foods—may have been part of Alpine life in the Copper Age, thousands of years before such practices were documented in Mediterranean or European lowland societies. This challenges conventional narratives about where and when fermentation technologies emerged.