Volatile Compounds Formation in Sparkling Wine

Abstract

Volatile compounds and sensory characteristics of sparkling wines present a strong link with the particularities of the Traditional, Charmat, Transfer, Ancestral, and Asti methods. The Traditional, Charmat, and Transfer methods involve a second alcoholic fermentation induced by adding sugar and yeast to a base wine, while the Ancestral and Asti methods occur by a single fermentation. The Asti wines are characterized by the presence of varietal compounds due to grapes of intense aroma. However, regardless of the production method, free varietal compounds (terpenes and C13-norisoprenoids) are released from glycosylated forms, and various classes of volatile compounds are formed (esters, alcohols, fatty acids, aldehydes, and ketones) during the fermentation stage. The Traditional and Transfer methods include the autolysis stage that plays an important role in the formation of volatile compounds through the hydrolysis of the glycosidic bond of varietal compounds and some esters, sorption of volatile hydrophobic compounds on the lees and esterification reaction. Two C13-norisoprenoids [1,1,6-trimethyl-1,2-dihydronaphthalene (TDN) and vitispirane] have been reported as the main markers of the autolysis process. The formation of volatile compounds is driven by the different stages/methods of sparkling wine production, in addition to the role of terroir, grape variety, yeast strain, and fermentation conditions, oenologist practices, among other factors.