Abstract:In this paper，sauce flavor Baijiu freshly brewed at fourth round and stored for 1 year and 3 years was used as the research object，and volatile aroma substances were analyzed by electronic nose and gas chromatography-ion mobility spectroscopy（GC-IMS），to explore the effect of storage time on volatile aroma substances of sauce flavor Baijiu.The electronic nose results showed that sensors W3C（sensitive to ammonia and aromatic substances），W5C（sensitive to alkanes and aromatic substances），W1W（sensitive to organic sulfides and terpenes）and W2S（sensitive to ethanol）had significant differences in the response values for sauce flavor Baijiu with different storage time（P<0.05），and the highest response value was observed for sauce flavor Baijiu stored for 3 years. Combined with relative odor activity value（ROAV）and variable importance in projection（VIP），the GC-IMS revealed that ethyl caproate，ethyl valerate，ethyl isovalerate，pentyl acetate and isobutyraldehyde were the key compounds with obvious contribution to the aroma of sauce flavor Baijiu.Ethyl isovalerate and ethyl isobutyrate had differences in contributing to the aroma of sauce flavor Baijiu with different storage time and they contributed more to that of sauce flavor Baijiu stored for 3 years（P<0.05）. 3-Methyl-1-butanol，furfural，ethyl isovalerate，ethyl 2-methylbutyrate，ethyl acetate and ethyl isobutyrate were the key differential compounds in sauce flavor Baijiu with different storage time and they were higher in sauce flavor Baijiu stored for 3 years.This indicated that storage has a positive effect on the formation of flavor quality of sauce flavor Baijiu，and the overall flavor of sauce flavor Baijiu stored for 3 years was prominent.