Yeast are humans’ oldest domesticated microorganism, and for thousands of years we have used them to produce many useful, and often delicious, products. But did you know yeast do more than just make your bread rise?

As yeast grow, they convert sugars primarily into carbon dioxide and alcohol, but through this process they also produce a huge variety of aromatic compounds. Some of these aromatics are fruity, and can also be found in apples, bananas, and berries. Other compounds may smell like cloves, herbs, or vegetables. And they can also make weird smells that you’d never associate with baking or brewing: from nail polish, to baby vomit, even the buttery smell of microwavable popcorn! Balancing all of these flavours is critical, and learning more about how and why yeast make them will help us breed better yeast strains for the breads and beers of tomorrow.

Dr. Karissa Milbury (@Point_Mutation) researches the complex aromas that are produced by Baker’s yeast (A.K.A.Saccharomyces cerevisiae, or brewer’s yeast) during fermentation, through her role as a Mitacs Postdoctoral Fellow at UBC and Renaissance BioScience Corp.