Hello there! I'm Dr. Vinifera, but you can call me Vinny. Ask me your toughest wine questions, from the fine points of etiquette to the science of winemaking. And don't worry, I'm no wine snob—you can also ask me those "dumb questions" you're too embarrased to ask your wine geek friends! I hope you find my answers educational, empowering and even amusing. And don't forget to check out my most asked questions and my full archives for all my Q&A classics.
Dear Dr. Vinny,
I have seen some wineries say that they use natural or native yeast for fermentation. Is that possible? I thought that natural yeast was difficult to control and that controlled yeast was preferred for fermentations.
—Dave, Oakland, Calif.
If left alone, grapes would eventually ripen, their skins would crack and the juice begin to ferment, thanks to the "native" yeasts that live on and around the vines. But most winemakers don't leave this process to chance; they make wine by inoculating the juice with known strains of "cultured" yeasts. These "lab yeasts" are desirable because they are strong, consistent, fast fermenters. That consistency is key, especially with producers who are making large volumes of wine.
Some winemakers prefer native (wild, indigenous, natural, ambient or spontaneous) yeast fermentation. Yeast populations are in the air; they can originate in the vineyard or in a cellar. The biggest benefit of wild yeast is complexity—some aromas, flavors and, in particular, textures seem unique to this method. But natural fermentations are riskier, slower and can be unpredictable.