Glycosidically Bound Volatile Aroma Compounds in Grapes and Wine: A Review

Volatile aroma compounds in plants are typically found both as free and bound to a sugar moiety. When bound, these compounds are not odor active; however, upon hydrolysis of the glycoside, these compounds may then be volatilized. In grapes and wine, a large proportion of volatile aroma compounds are found in the bound form. A review of glycosides in grapes and in wine is presented with a focus on identified glycoside structures, their biosynthesis, their potential roles in the plant, and methods for their analysis. Studies of these compounds and their concentration changes during the winemaking process are discussed.