Analysis of the Key Odorants in Amomum tsaoko Cobs Treated by Different Enzymes

To identify the key odorants in Amomum tsaoko cobs (ATC) before and after enzymatic treatment, solvent extraction (SE) followed by solvent-assisted flavor evaporation (SAFE) combined with gas chromatography-mass spectrometry-olfactometry (GC-MS-O) was used to extract and analyze volatile components in ATC. A total of 82 compounds were identified, including 32 odor-active compounds. Quantitative analysis was conducted by the internal standard method, and the concentrations of odor-active compounds in fresh ATC, and ATC treated by cellulase, β-glucosidase or their mixture were 237562.17, 220738.79, 296759.57 and 284809.47 μg/kg, respectively. Based on their concentrations and thresholds, odor activity values (OAVs) were calculated, and 19 odorants with OAV equal to or greater than 1 were determined as the key odorants of ATC. The numbers of key odorants in fresh ATC, and ATC treated by cellulase, β-glucosidase or their mixture were 16, 15, 16 and 15, respectively. Because of their different key odorants, the extracts had different odor characteristics. Different enzymes should be selected for the extraction of aroma components from ATC according to practical needs.