Sugars in wine Sugars in wine Sugars in wine are at the heart of what makes winemaking possible. During the process of fermentation, sugars from wine grapes are broken down and converted by yeast into alcohol (ethanol) 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 (separated) by the enzyme invertase into glucose and fructose. By the time of harvest, between 15 and 25% of the grape will be composed of simple sugars. Both glucose and fructose are six-carbon
Wine Grapes to a connection between the Italian variety Primitivo and the Croatian wine grape Crljenak Kaštelanski. After years of research and DNA testing of vines from vineyards across the globe, a single 90-year-old grape vine from the garden of an elderly lady in Split, Croatia provided the evidence to show that Zinfandel was originally a Croatian grape known as "Tribidrag" that had been cultivated in Croatia since the 15th century. Other findings reported in "Wine Grapes" include the discovery of several species of Malvasia grapes growing in central and southern Italy are actually the Spanish wine grape Tempranillo and that Cabernet