title: Metabolomic profiling delineate taste qualities of tea leaf pubescence.
abstract: The amount of pubescence on leaf epidermis is an important morphological marker for the quality of green tea, and the tea with plenty of pubescence is generally recognized as having a better taste. However, there is no systematic study on chemical compositions of tea leaf pubescence. The contributions of pubescence to taste properties are far from clear. In this research, 114 components were identified from the tea leaf pubescence of yunkang 10, a broad-leaf tea cultivar with plenty leaf pubescence, for the first time with a non-targeted metabolomics approach using ultra-high performance liquid chromatography-quadrupole-time-of-flight mass spectrometry (UHPLC-Q-TOF-MS). Compared to the tea leaf with the pubescence removed (non-pubescent leaf), the pubescence obtained from the same shoots had relatively higher contents of amino acids and lower contents of polyphenols. It was also found that the umami of pubescence was elevated, while the bitterness and astringency were significantly declined. Partial least-squares (PLS) analysis suggested that the polyphenols and amino acids accounted for the taste quality. To the best of our knowledge, this is the first time that the metabolites in tea leaf pubescence were profiled. The results offer the direct concrete evidence on the contributions of pubescence to the tea taste properties.
authors.affiliation: State Key Laboratory of Quality Research in Chinese Medicine, Macau Institute for Applied Research in Medicine and Health, Macau University of Science and Technology, Avenida Wai Long, Taipa 999078, Macau, China.
authors.forename: Mingzhi
authors.initials: M
authors.lastname: Zhu
authors.affiliation: State Key Laboratory of Quality Research in Chinese Medicine, Macau Institute for Applied Research in Medicine and Health, Macau University of Science and Technology, Avenida Wai Long, Taipa 999078, Macau, China. Electronic address: nli@must.edu.mo.
authors.forename: Na
authors.initials: N
authors.lastname: Li
authors.affiliation: College of Longrun Pu-erh Tea, Yunnan Agricultural University, Kunming, Yunnan 650201, China.
authors.forename: Ming
authors.initials: M
authors.lastname: Zhao
authors.affiliation: State Key Laboratory of Quality Research in Chinese Medicine, Macau Institute for Applied Research in Medicine and Health, Macau University of Science and Technology, Avenida Wai Long, Taipa 999078, Macau, China.
authors.forename: Wenliang
authors.initials: W
authors.lastname: Yu
authors.affiliation: State Key Laboratory of Quality Research in Chinese Medicine, Macau Institute for Applied Research in Medicine and Health, Macau University of Science and Technology, Avenida Wai Long, Taipa 999078, Macau, China. Electronic address: jlwu@must.edu.mo.
authors.forename: Jian-Lin
authors.initials: JL
authors.lastname: Wu
mesh_terms: D000328:Adult; D000596:Amino Acids / Q000032:analysis; D028241:Camellia sinensis / Q000033:anatomy & histology / Q000737:chemistry*; D002851:Chromatography, High Pressure Liquid; D005260:Female; D006801:Humans; D008297:Male; D013058:Mass Spectrometry; D019441:Plant Epidermis / Q000033:anatomy & histology*; D010936:Plant Extracts / Q000032:analysis; D018515:Plant Leaves / Q000033:anatomy & histology / Q000737:chemistry*; D018520:Plant Shoots / Q000033:anatomy & histology / Q000737:chemistry; D059808:Polyphenols / Q000032:analysis; D013649:Taste; D013662:Tea / Q000737:chemistry*; D055815:Young Adult
chemical_list: D000596:Amino Acids; D010936:Plant Extracts; D059808:Polyphenols; D013662:Tea
keywords: Amino acids; Metabolites; Polyphenols; Taste analysis; Tea leaf pubescence; UHPLC-Q-TOF-MS