Yeast may be small, but their impact on beer—and brewing history—is enormous. In this presentation, we’ll take a deep dive into the fascinating technical journey of brewers yeast. We’ll begin with the early days of microbiology, tracing the path from the discovery of invisible life forms to the realization that yeast are responsible for fermentation, transforming wort into the beer we love.

We’ll explore the evolutionary tree of Saccharomyces species and uncover how different strains of yeast give rise to the wide diversity of beer styles. Special focus will be given to the differences between ale and lager yeasts, both in how they behave and in their genetics. You’ll learn how Saccharomyces pastorianus, the yeast behind lagers, is a hybrid between S. cerevisiae and the cold-tolerant S. eubayanus, and how scientists believe this unusual pairing came to be.

The talk concludes with a look at the cutting edge of yeast science. We’ll discuss how brewers and scientists are now pushing boundaries with genetic engineering, and the creation of novel hybrids, opening new possibilities for flavor, efficiency, and sustainability in brewing.

Jonathan Hughes, Ph.D., is the Director of Food and Agriculture Programs at UC Davis Continuing and Professional Education and the microbiology instructor for the Master Brewers Certificate Program. He entered the brewing industry in 2013, when, as a graduate student in microbiology at UC Davis, he founded the QA/QC laboratory at Heretic Brewing Company in Fairfield, California. Before joining Continuing and Professional Education, Hughes served as the quality assurance manager at Heretic while teaching introductory brewing and microbiology classes at UC Davis, Sacramento State University and Sacramento City College.

Reach out to Jon at jghughes@ucdavis.edu