Abstract:In order to distinguish and protect the tea products of origin, this study established a method of tea composition difference analysis based on mass spectrometry full scanning combined with systematic clustering. Green tea from Three Gorges Reservoir Area was chosen to be the research object. High-performance liquid chromatography tandem high-resolution mass spectrometry was used for chemical full-scan analysis, and 65 chemical components of tea were confirmed; combining principal component analysis and partial least squares method, a correlation analysis model of geographical origin and component correlation of tea was established. 13 feature components related to geographical information were screened. Through further quantitative analysis, it is finally determined that epicatechin, EGCG, theophylline, glutamate, quercetin, caffeic acid, rutin, chlorogenic acid and gallic acid have a good distinction among the selected tea from different geographical sources. This method is efficient, stable and specific, and provides a supplement for the study of the material basis and geographical traceability of tea products.