Abstract:In order to analyze the characteristics of aroma volatile components and key aroma components of black tea from different tea tree varieties in Guangxi, The 12 black tea samples of different varieties in Guangxi province, were identified with sensory quality evaluation combined with headspace solid-phase microextraction (HS-SPME) coupled with gas chromatography-mass spectrometry (GC-MS), and the samples were analyzed by hierarchical cluster analysis and orthogonal partial least squares discrimination analysis (OPLS-DA). The results showed that different varieties of black tea aroma quality were different, the black tea mainly presented floral fruity, and sweet aromas, The sensory quality of Wu Niuzao black tea was the best, followed by Huang Guanyin, the total score was 91.20, 90.55, respectively, and the Wu Niuzao was representative of sweet black tea, Huang Guanyin was representative of floral, fruity black tea. A total of 40 aroma compounds were detected including alcohols, aldehydes, ketones, esters, olefins, pyrroles and their derivatives, and others. Among them, alcohols, esters, and aldehydes were the main aroma contributors substances, and their relative content was 59.84%-79.21%, 3.80%-17.68%, and 2.93%-16.65%, respectively. OPLS-DA models, which enabled the effective distinguishing of sweet-odor black tea and floral fruity-odor black tea, were constructed based on the relative contents of 33 common aroma compounds. Dehydrolinalool, linalool oxidized II, linalool oxide Ⅰ, geraniol, methyl salicylate, (E)-2-hexenal, linalool, and β-ionone, and were identified as the key differentiating compounds between the two types of black tea of floral fruity-odor and sweet-odor.
