The Fascinating Role of Yeast in Winemaking

In this episode of After Wine School, host Keith Wallace, joined by fermentation expert Alana Zerbe, delves deep into the critical role yeast plays in winemaking. They explore why wines have distinct smells, how yeast converts grape sugars into alcohol, and the influence yeast has on flavors, mouthfeel, and terroir. The discussion covers the complexity of Saccharomyces cerevisiae, native yeasts, and the impact of fermentation temperatures. They also discuss the nuances of wild yeast fermentations, stuck fermentations, and the presence of Brettanomyces. The episode concludes with a lightning round exploring the yeast characteristics of various wine styles. Wine lovers and aspiring winemakers will gain a thorough understanding of the science behind their favorite wines.

00:00 Introduction