关键词: 福鼎白茶, 挥发性萜类化合物, 对映异构体, 多元统计分析, 手性气相色谱-质谱联用技术

Abstract: In this work, the enantiomeric distribution of 14 volatile terpenoids in different types of Fuding white teas were analyzed by headspace-solid-phase microextraction (HS-SPME) and enantioselective gas chromatography-mass spectrometry (GC-MS). The relative quantitative analysis results showed that S-linalool, S-Z-nerolidol and (2S,5R)-linalool oxide B were relatively more abundant in most white teas, while the contents of four enantiomers of theaspirane were extremely low. The enantiomeric analysis results indicated that S-limonene, (2S,5S)-linalool oxide A, (2S,5R)-linalool oxide B, S-linalool, (2R,5R)-theaspirane A, (2R,5S)-theaspirane B, R-terpinen-4-ol, S-α-terpineol, S-citronellol, S-α-ionone, S-Z-nerolidol, S-E-nerolidol, (1R,2R)-methyl jasmonate and (1R,2S)-methyl epijasmonate were the major absolute configurations of terpenes in most white teas, and that the enantiomeric ratios (ERs) of linalool, linalool oxide B, terpinen-4-ol, citronellol, α-ionone, linalool oxide A and Z-nerolidol were related to the plucking standard of white teas. Moreover, multivariate statistical analysis exhibited that a significant difference in the contents of 12 volatile terpenoid enantiomers existed among the three different types of Fuding white teas. R-Linalool, (2R,5S)-theaspirane B, S-α-terpineol, R-E-nerolidol, R-Z-nerolidol, S-limonene and S-E-nerolidol presented the highest levels in Silver Needle tea samples, while the opposite was true for (2R,5R)-linalool oxide A and (2S,5R)-theaspirane B. S-Z-Nerolidol and (1S,2S)-methyl epijasmonate showed higher contents in White Peony tea samples, and the content of R-α-ionone was higher in Shou Mei tea samples than in the other types. The above studies provide the theoretical foundation for further understanding the formation mechanism of the aroma quality of, discriminating the types and grades of and establishing a fingerprint for white teas.

Key words: Fuding white tea, volatile terpenoids, enantiomer, multivariate statistical analysis, enantioselective gas chromatography-mass spectrometry