Analysis of Characteristic Volatile Components of Three Kinds of Black Tea Based on HS-SPME-GC-MS and Multivariate Statistics

Headspace solid-phase microextraction (HS-SPME) and gas chromatography-mass spectrometry (GC-MS) combined with multivariate statistical analysis were used to explore the differences in the volatile components of three kinds of black tea, including Keemun black tea, GABA black tea, and Yunnan black tea. GC-MS results showed that a total of 78 volatile components were identified, including hydrocarbons, terpenes, alcohols, esters, ketones, aldehydes, heterocyclic compounds, and phenols. The total volatile substances of three kinds of black tea were similar in quantity, but their content was quite different, and the common volatile components mainly include linalool, geraniol, nonanal, methyl salicylate, linalool oxide, etc. The results of multivariate statistical analysis showed that GABA black tea, Yunnan black tea, and Keemun black tea could be distinguished according to the volatile components. Partial least squares discriminant analysis screened 12 differential volatile components, including neryl acetate, methyl salicylate, isoborneol, linalool, citral, etc. Neryl acetate and citral had the highest content in Keemun black tea, which helped to form the floral and fruity aroma type of Keemun black tea. Isoborneol and linalool had the highest content in Yunnan black tea. The content of linalool and methyl salicylate was high in GABA black tea, which was conducive to the formation of the fresh and tender floral and fruity aroma of GABA black tea. The results of this study can lay a theoretical foundation for scientifically and objectively evaluating the aroma characteristics of GABA black tea, clarifying the difference in aroma quality between Keemun black tea, GABA black tea, and Yunnan black tea, and constructing the flavor quality identification map of different types of black tea.