关键词: 铁观音；红茶；乌龙茶；加工工艺；香气；溶剂辅助风味蒸发；气相色谱-质谱/火焰离子化检测器

Abstract: In this study, the aroma quality of oolong tea, black tea and green tea manufactured from the fresh leaves of Camellia sinensis cv. Tieguanyin was determined by sensory evaluation, and their volatile compounds were determined by solvent-assisted flavor evaporation combined with gas chromatography-mass spectrometry/flame ionization detector. We found that all the Tieguanyin tea samples scored 90 points for aroma with a flowery note. In total, 52 volatile components were detected in the tea samples, with linalool and fatty acid esters being the major ones. The characteristic aroma components of Tieguanyin tea included oxidized linaool II, oxidized linaool IV, linalool, trans-nerolidol, hexanoic acid 3-hexenyl ester, hexanoic acid 2-hexenyl ester, benzoate 3-hexen-1-ol, benzoic acid hexyl ester and neophytadiene. Black tea processing could promote the formation of linalool and its oxides, butanoic acid 3-methyl-, 2-hexenyl ester, hexanoic acid 3-hexenyl ester, hexanoic acid 2-hexenyl ester, neophytadiene, dihydroactinidiolide, beta-ionone, methyl salicylate. Oolong tea processing was conducive to the formation of hotrienol, 2,6-dimethyl-3,7-octadiene-2,6-diol, trans-nerolidol, octanoic acid 3-hexenyl ester, and benzoic acid hexyl ester. In conclusion, the aroma characteristics of Tieguanyin tea were closely related to its species-specific components and the manufacturing technology used; which will provide an important technical reference for the development of new Tieguanyin tea.

Key words: Tieguanyin tea; black tea; oolong tea; manufacturing technology; aroma; solvent-assisted flavor evaporation; gas chromatography-mass spectrometry/flame ionization detector