Abstract: In this paper, Cabernet sauvignon grapes from the north foot of Tianshan Mountain in Xinjiang and Rushan region in Shandong were fermented with Saccharomyces cerevisiae and Torulaspora debrueckii alone and in combination, respectively. Physicochemical properties and volatile contents of the resulting wines were analyzed. The results showed that a total of 60 volatile compounds related to the metabolism of yeasts were detected in all wines, including 23 alcohols, 26 esters, 8 acids and 3 ketones. The aroma components of wines fermented with different yeast strains were significantly different. The wine produced using Torulaspora debrueckii alone showed significantly higher contents of esters, alcohols and acids, whereas that produced by mixed culture fermentation showed lower contents of volatile acids. Torulaspora debrueckii produced a wine that was richer in ethyl esters, especially fatty acid ethyl esters such as ethyl octanoate, ethyl decanoate and ethyl dodeconoate, increasing the fruity flavor. Mixed culture fermentation could enhance the fermentation aroma of wines and increase its complexity irrespective of the geographical origin of grapes.

Key words: Torulaspora debrueckii, mixed culture fermentation, wine, fermentation aroma, gas chromatography-mass spectrometry (GC-MS)