Ancient yeast from Iceman's remains baked into modern bread

Scientists have isolated yeast living in the preserved remains of Ötzi the Iceman, the 5,300-year-old mummy discovered in 1991 on a glacier in the Schnal Valley on the border between Austria and Italy, and used the microbes to bake sourdough bread. According to Phys.org and the Jerusalem Post, the yeast has been growing in Ötzi's gut for millennia, preserved in the frozen conditions of the high Alps until his recovery and subsequent study.

Ötzi's remains are now housed at the Archaeological Museum of Bolzano, where they remain one of Europe's most significant Bronze Age finds. The mummy was discovered with clothing, tools and weapons intact, offering an unparalleled window into Alpine life before recorded history. The recent cultivation of the yeast represents a novel use of the body's biological material for scientific and culinary experiment.

The work marks an unusual intersection of archaeology, microbiology and food science. The yeast cultures, once isolated from Ötzi's digestive tract, proved viable enough to ferment dough, producing a functioning sourdough starter. Scientists told AFP they successfully baked bread using the ancient microbe, demonstrating that even after five millennia of preservation, the yeast retained its metabolic properties.

The discovery underscores the exceptional preservation conditions of the high-altitude glacier where Ötzi was found. The extreme cold and dryness of the Alpine environment halted decomposition and microbial growth, allowing organic material—including the bacteria and fungi colonizing the body—to survive intact. For Bolzano's museum, which has curated Ötzi since his transfer to Italy, the finding adds another layer of scientific value to an already extraordinary specimen.

The work also illuminates the microbial ecology of the Bronze Age. Ötzi's gut flora offers clues to diet, environment and disease burden in a population living at the edge of the habitable Alpine zone. The yeast species identified in his remains may have come from fermented foods or contaminated water supplies, or colonized the body after death during the initial stages of mummification. The successful cultivation and use of the microbe in modern baking, however, speaks more to the resilience of ancient yeast than to any culinary practice Ötzi himself might have known.