Identification of Four Kind Key Aroma Components of Wuyi Rock Tea Based on HS-SPME-GC-MS and OAV

In this study, headspace solid phase microextraction gas chromatography mass spectrometry (HS-SPME-GC-MS) was used to identify the volatile substances of four Wuyi rock teas varieties, and the key aroma components were screened by principal component analysis (PCA) and aroma activity value (OAV). The results showed that 303 kinds of known volatile substances were detected in four Wuyi rock teas varieties by GC-MS, including esters, pyrrole, alcohols, hydrocarbons, ketones, alkanes, aldehydes, etc. The relative contents of esters and alcohols were higher than others. 55 volatile substances with VIP>1 were screened by PCA analysis, 29 volatile substances were screened by OAV analysis. Based on VIP>1 values and OAV>1 analysis, a total of 17 characteristic volatiles were identifified. Meantime, the clusting analysis results showed that 2-n-pentylfuran, indole, trans violet ketone, phenylethyl acetate, cis-3-hexenol benzoate, 6-methyl-5-hepten-2-one, geranyl acetone, phenylacetaldehyde, hexyl caproate, phenylacetonitrile and isoeugenol might be the characteristic volatiles that form the different aroma profifile of dahongpao. α-Farnesene and geraniol might be the characteristic components that form the different aroma of Rougui. α-Farnesene, (trans, trans) 3,5-octadiene-2-one might be the characteristics of Huanghua Rougui. Linalool and n-valeric acid might be the characteristics of Shuixian. These results would provide a reference for analyzing the characteristic aroma and quality control of Wuyi rock teas.