What is the yeast used in wine?

The answer could be easy: Saccharomyces cerevisiae. End of question.

Well, it is not that easy. Yes, Saccharomyces cerevisiae is able to transform sugar into alcohol and is the yeast that makes bread rise, but this one special yeast is actually very sensitive to DNA mutations. Mutations that ultimately create several hundred strains of yeast.

Do not worry, I am not going to list them all below because when it comes to wine for the consumer, it is not really about knowing what the yeast is, but actually knowing where the yeast is from.

What is wine yeast? “Native yeast” vs “Added yeast”.

You may have heard your local wine retailer talking about the quality of wine made with “native yeast”. What does that mean?

Yeast is a living organism naturally present on the skin of grape berries. When the grapes are crushed the yeast is then found in the wine must (the grape juice resulting from the crushing). From there, the fermentation process can spontaneously occur. In some cases, the winemaker might use a “pied de cuve”. “Pied de cuve” roughly translates to “foot of tank”. The idea is to develop a viable population of yeast to ensure a good fermentation process and make sure it is steady and complete.