Characterization of the key aroma compounds in aged Chinese Xiaoqu Baijiu by means of the sensomics approach

The aromatic characteristics of Xiaoqu Baijiu differ noticeably and were investigated using the sensomics approach. Aroma extract dilution analysis revealed more aroma-active compounds in aged Xiaoqu Baijiu than fresh Xiaoqu Baijiu, with 55 compounds identified with flavor dilution (FD) factors of ≥8. Using sensomics, 51 odorants were identified as important aroma compounds in aged Xiaoqu Baijiu. Omission models suggested that 3-hydroxy-4,5-dimethyl-2(5H)-furanone (sotolon), vanillin, and 3-(methylthio)propionaldehyde (methional) played critical roles in the overall aroma characteristics of aged Xiaoqu Baijiu. Furthermore, 1,1-dimethoxyethane, 3-methylbutanal, dimethyl trisulfide, ethyl acetate, and ethyl isovalerate also exhibited significant roles in the aroma characteristics of aged Xiaoqu Baijiu. This work may provide a better understanding on Chinese Xiaoqu Baijiu and the changes of aroma compounds during the aging process of liquor.