Sugars in wine

The sugars in wine grapes are what make winemaking possible. During the process of fermentation, sugars are broken down and converted by yeast into alcohol and carbon dioxide. Grapes accumulate sugars as they grow on the grapevine through the translocation of sucrose molecules that are produced by photosynthesis from the leaves. During ripening the sucrose molecules are hydrolyzed (inverted) by the enzyme invertase into glucose and fructose.