VATIS UPDATE Article

A lab team at the Pacific Northwest Diabetes Research Institute, the United States, recently tested unroasted coffee and cacao beans from around the world for Saccharomyces cerevisiae, the yeast used in baking, brewing and winemaking. “The first really interesting thing we noticed was that they were all very different from each other. So a coffee strain from Colombian coffee was very similar to other Colombian strains, but it was really different from Yemeni coffee,” said lab director and study co-author Aimée Dudley. The variations are so obvious that the team can tell the origin of a bean based only on the DNA of its resident S. cerevisiae.

That’s surprising because the varieties of the same species found on wine grapes are very similar, whether they come from California, Australia or anywhere else. “Wine production was perfected and developed very early in human history, and as humans migrated across the planet they brought not only those grape vines but the strains of yeast with them,” said Dudley. The S. cerevisiae strains her team uncovered on the coffee and cacao, on the other hand, have a mix of wine yeast DNA and local wild yeasts. Despite their strong similarities, different wine yeasts produce varied flavors out of the same grapes.