Fermentation is a key process in wine making where grape must is transformed into wine. During the process, yeast converts sugar from the grape must into alcohol and carbon dioxide. In addition to producing alcohol, the chemical reaction also affects the flavor, aroma, and color of the wine.
Wine fermentation has two stages – a primary and a secondary fermentation and usually is finished after 2-3 weeks. Temperature and exposure to oxygen are important factors for the process, which can result in wine faults if the winemaker is not attentive.
Fermentation can be done in stainless steel tanks, wood barrels, clay vessels like qvevri or amphora or in the bottle if you want to keep the carbon dioxide for sparkling wines like Pét-Nat.
