Abstract:To explore the effects of different yeast strains on the aroma quality of distilled spirit produced from Yantai Red Fuji apples, fermentation trials were performed with yeast strains BV818, F33, IONYS, FC9 and EC1118. The results demonstrated that IONYS had strong fermentation capacity, reaching the maximum alcohol content of 13.30%vol on day 8, accompanied by low residual sugar of 0.37?g/L. F33 was second only to IONYS in alcohol-producing ability, with an alcohol content of 13.01%vol and residual sugar of 0.45?g/L on day 8. A total of 56 volatile compounds were identified in apple distilled spirits by gas chromatography-mass spectrometry (GC-MS). The numbers of volatile compounds detected for each yeast strain were 49 for BV818, 48 for F33, 52 for IONYS, 50 for FC9 and 40 for EC1118. Six shared components, namely ethyl octanoate, ethyl decanoate, ethyl 9-decenoate, ethyl hexanoate, isoamyl acetate and ethyl laurate, exhibited Odor Activity Value (OAV) > 1, which collectively endowed the spirit with fruity notes of banana, pineapple, citrus and other fruits. Electronic nose results indicated that the apple distilled spirit fermented by IONYS contained higher levels of alcohols, aldehydes, ketones, inorganic sulfides, nitrogen oxides, short-chain alkanes, aromatic compounds and organic sulfides. Sensory evaluation showed significant differences in flavor characteristics among samples from different yeast strains. The FC9-fermented spirit presented prominent fruity and floral aromas, the F33-fermented spirit had excellent fermented aroma, whereas the IONYS sample featured well-balanced aromas and the optimal comprehensive quality. Saccharomyces cerevisiae strains are the key core factor determining the aroma, flavor and quality of apple distilled spirits, and exert a decisive effect on shaping the flavor profile of the spirit.