The Longer the Storage Time, the Higher the Price, the Better the Quality? A 1 H-NMR Based Metabolomic Investigation of Aged Ya'an Tibetan Tea ( Camellia sinensis ).

As an essential beverage beneficial for Tibetan people, Ya'an Tibetan tea has received scarce attention, particularly from the point of view of the characterization of its metabolome. The aim of the study is to systematically characterize the metabolome of Tibetan tea by means of untargeted 1 H-NMR. Moreover, the variations of its metabolome along ageing time are evaluated by taking advantage of univariate and multivariate analyses. A total of 45 molecules are unambiguously identified and quantified, comprising amino acids, peptides and analogues, carbohydrates and derivates, organic acids and derivates, nucleosides, nucleotides and catechins. The concentrations of amino acids, organic acids, carbohydrates and catechins are mainly determined by ageing time. The present study would serve as a reference guide for further work on the Ya'an Tibetan tea metabolome, therefore contributing to the related industries.