Differences in taste characteristics and antioxidant properties of four substitute teas based on a targeted metabolomics approach

To investigate the differences in taste characteristics and antioxidant properties of four types of tea substitutes. After sensory review and electronic tongue indicated that the taste characteristics of the four substitute teas was sweetness, bitterness and astringency. There were a total of 136 flavonoid metabolites in 12 categories and 12 sugar metabolites were identified in the four substitute teas with ultra-performance liquid chromatography tandem-mass spectrometry metabolomics targeted detection. Flavonoids were significantly positively correlated with antioxidant properties, among them, 15 were positively associated with clearing ABTS radicals and 5 were positively associated with clearing DPPH radicals, and sugars were significantly negatively correlated with antioxidant properties. The antioxidant properties were in the following order: TC > KD > LY > QQ. Conclusion: Significant differences in the content of flavonoids and sugar metabolites are the main reasons for the formation of the flavour characteristics and antioxidant differences of the four substitute teas.