Wine Glossary
Definition: Fermentation
During the primary fermentation of wine, the two natural grape sugars, glucose and fructose are converted to alcohol (ethanol) by the action yeast. The by-products of primary fermentation are aromas and flavors, the gas carbon dioxide, and heat. The longer you ferment the grape sugers the higher the wines alcohol content will be.
Source: Primary Fermentation of Wine - Richard Gawel
