HS-SPME and SDE combined with GC–MS and GC-O for characterization of flavor compounds in Zhizhonghe Wujiapi medicinal liquor

Volatile compounds in Chinese medicinal liquor, Zhizhonghe Wujiapi (WJP liquor), were extracted by headspace-solid-phase microextraction (HS-SPME) and simultaneous distillation and extraction (SDE), respectively, and identified and quantified by gas chromatography-mass spectrometry (GC–MS) and gas chromatography–olfactometry (GC-O). Results showed that a total of 133 volatile compounds (i.e., 99 by HS-SPME, 67 by SDE, and 33 by both) including esters, alcohols, acids, aldehydes, ketones, furans, terpenes, and other miscellaneous compounds were identified by GC–MS. A total of 66 aroma active compounds were further recognized by GC-O, and 43 of them were confirmed as key aroma compounds owing to their high OAV values. After making a simulated reconstitute by mixing 31 characterized aroma compounds (OAVs ≥ 1) based on their measured concentrations, the aroma profile of the reconstitute showed a good similarity to the aroma of the original WJP liquor. Omission test further corroborated 25 key aroma-active compounds in the WJP liquor. The analysis of the volatile components of this special Chinese medicinal liquor is expected to provide some insights in terms of its quality improvement and aroma profile optimization.