Characterization of key aroma compounds in Laobaigan Chinese Baijiu by GCxGC-TOF/MS and means of molecular sensory science

Laobaigan (LBG) Baijiu is recognized as one of the famous Chinese liquors due to its unique flavor characteristics. However, its key aroma-active volatiles are still unknown. In this study, 414 volatile chemicals in the LBG Baijiu were initially detected by comprehensive two-dimensional gas chromatography-time-of-flight mass spectrometry (GCxGC-TOF/MS). Then, 52 of them were determined by sample dilution analysis (SDA) for screen of aroma-active compounds. Based on their odor-activity values (OAVs) that were determined by the external standard method performed on the GCxGC-TOF/MS, 32 volatile compounds were further recognized as important odorants, which were reconstituted to simulate and validate the aroma profile of the LBG Baijiu. Moreover, omission experiments were conducted to corroborate the importance of key odorants. As a result, nine aroma compounds were finally confirmed as the key aroma-active compounds of the LBG Baijiu.