What the Pros Think When They Choose Yeast

According to academics and professionals, if you want to pick the right yeast for your grape juice, knowing what questions to ask is essential. “I view it more as not who do I rule in, but more who do I rule out?” said Dr. Linda Bisson, professor of enology at University of California, Davis, whose specialty is yeasts. “There’s all these factors to take into account,” said Lucy Joseph, who is the curator for the UC Davis enology department’s collection of cultures, which includes both yeasts and spoilage microbes. There are also many, many different strains of wine yeast from which to choose. Yeast companies bank hundreds of strains, but most of these aren’t available to the home winemaker. The main job of yeast is to ferment the wine, changing the sugars in the grape juice to alcohol. Because yeast is a living organism, it needs the same two things to survive: carbon, which in the case of yeast means sugar, and nitrogen. “You’re growing yeast in this juice and you want it to be happy,” Joseph said. But yeast