Exploring authenticity and potential markers of Lushan Yunwu green tea by fusing 1H NMR and UPLC-Q/TOF-MS techniques

Lushan Yunwu green tea is a top-quality green tea produced in the famous Lushan Mountain, but there are many counterfeit green teas posing as Lushan Yunwu green tea on the market. Therefore, a combination of 1H NMR and UPLC-Q/TOF-MS was used to identify the authenticity of Lushan Yunwu green tea and obtain a more comprehensive screening of markers. Data fusion improved the classification performance of a single instrument in distinguishing Lushan Yunwu green tea from counterfeit ones. The OPLS-DA model's performance parameters were significantly enhanced through mid-level data fusion (R2Y = 0.982, Q2 = 0.96). Further screening based on mid-level data fusion obtained 10 markers of Lushan Yunwu green tea, including methyl gallate, epigallocatechin gallate, 1,3,6-tri-O-galloylglucose, hydroxyjasmonic acid glucoside, and chlorogenic acid, etc. The dataset of these 10 markers could effectively distinguish Lushan Yunwu green tea from counterfeit ones (classification accuracy = 100%). This provides new insights into tea authenticity identification.