The Hidden Microbes That Decide How Sourdough Tastes
January 21, 2026 | Source: Science Daily | by American Society for Microbiology
Sourdough starter is a simple blend of flour and water that bakers rely on to make bread rise. For scientists, it is also a powerful way to study how living organisms change over time. The familiar chewy texture and tangy flavor of sourdough come from a complex mix of microorganisms that ferment the dough. Research over the years has uncovered more than 60 types of bacteria and over 80 kinds of yeast in sourdoughs from different regions of the world. “We can use sourdough as an experimental evolution framework, to see what happens over time,” said evolutionary biologist Caiti Heil, Ph.D.
In a recent study published in Microbiology Spectrum, Heil and researchers at North Carolina State University in Raleigh set out to explore how flour choice affects the microbes living in sourdough starters. Their analysis showed that yeasts from the genus Kazachstania were consistently the most common across all starters. In contrast, the bacterial communities varied depending on the type of flour used.