title: The study of fingerprint characteristics of Dayi Pu-Erh tea using a fully automatic HS-SPME/GC-MS and combined chemometrics method.
abstract: The quality of tea is presently evaluated by the sensory assessment of professional tea tasters, however, this approach is both inconsistent and inaccurate. A more standardized and efficient method is urgently needed to objectively evaluate tea quality. In this study, the chemical fingerprint of 7 different Dayi Pu-erh tea brands and 3 different Ya'an tea brands on the market were analyzed using fully automatic headspace solid-phase microextraction (HS-SPME) combined with gas chromatography-mass spectrometry (GC-MS). A total of 78 volatiles were separated, among 75 volatiles were identified by GC-MS in seven Dayi Pu-erh teas, and the major chemical components included methoxyphenolic compounds, hydrocarbons, and alcohol compounds, such as 1,2,3-trimethoxybenzene, 1,2,4-trimethoxybenzene, 2,6,10,14-tetramethyl-pentadecane, linalool and its oxides, α-terpineol, and phytol. The overlapping ratio of peaks (ORP) of the chromatogram in the seven Dayi Pu-erh tea samples was greater than 89.55%, whereas the ORP of Ya'an tea samples was less than 79.10%. The similarity and differences of the Dayi Pu-erh tea samples were also characterized using correlation coefficient similarity and principal component analysis (PCA). The results showed that the correlation coefficient of similarity of the seven Dayi Pu-erh tea samples was greater than 0.820 and was gathered in a specific area, which showed that samples from different brands were basically the same, despite have some slightly differences of chemical indexes was found. These results showed that the GC-MS fingerprint combined with the PCA approach can be used as an effective tool for the quality assessment and control of Pu-erh tea.
authors.affiliation: Faculty of Life Science and Technology, Kunming University of Science and Technology, Kunming, Yunnan, People's Republic of China; Kunming Grain & Oil and Feed Product Quality Inspection Center, Kunming, Yunnan, People's Republic of China.
authors.forename: Shidong
authors.initials: S
authors.lastname: Lv
authors.affiliation: Faculty of Life Science and Technology, Kunming University of Science and Technology, Kunming, Yunnan, People's Republic of China.
authors.forename: Yuanshuang
authors.initials: Y
authors.lastname: Wu
authors.affiliation: Faculty of Life Science and Technology, Kunming University of Science and Technology, Kunming, Yunnan, People's Republic of China.
authors.forename: Jiangsheng
authors.initials: J
authors.lastname: Zhou
authors.affiliation: Faculty of Life Science and Technology, Kunming University of Science and Technology, Kunming, Yunnan, People's Republic of China.
authors.forename: Ming
authors.initials: M
authors.lastname: Lian
authors.affiliation: Yunnan Tasly Deepure Biology Tea Technology Limited Incorporation, Puer, Yunnan, People's Republic of China.
authors.forename: Changwen
authors.initials: C
authors.lastname: Li
authors.affiliation: Yunnan Tasly Deepure Biology Tea Technology Limited Incorporation, Puer, Yunnan, People's Republic of China.
authors.forename: Yongquan
authors.initials: Y
authors.lastname: Xu
authors.affiliation: Yunnan Tasly Deepure Biology Tea Technology Limited Incorporation, Puer, Yunnan, People's Republic of China.
authors.forename: Shunhang
authors.initials: S
authors.lastname: Liu
authors.affiliation: Yunnan Tasly Deepure Biology Tea Technology Limited Incorporation, Puer, Yunnan, People's Republic of China.
authors.forename: Chao
authors.initials: C
authors.lastname: Wang
authors.affiliation: Faculty of Life Science and Technology, Kunming University of Science and Technology, Kunming, Yunnan, People's Republic of China.
authors.forename: Qingxiong
authors.initials: Q
authors.lastname: Meng
mesh_terms: D028241:Camellia sinensis / Q000737:chemistry*; D063427:Food Quality; D008401:Gas Chromatography-Mass Spectrometry; D025341:Principal Component Analysis; D015203:Reproducibility of Results; D052617:Solid Phase Microextraction / Q000379:methods; D013662:Tea / Q000737:chemistry*
chemical_list: D013662:Tea