Abstract:The differential non-volatile compounds among Xinyang Maojian tea (XYMJ) with refreshing, orchid-like and tender corn-like aroma were identified by ultra-high performance liquid chromatography-Q-Exactive-mass spectrometry (UHPLC-Q-Exactive-MS). A total of 177 chemical compounds were identified in the XYMJ teas with different aroma types, 24 of which were found to show significantly different among the XYMJ tea samples, including 11 flavonoids, 7 amino acids and their derivatives, 2 sugars and their derivatives, and 4 other kinds. There were 7 differential compounds between the refreshing and tender corn-like XYMJ teas, 5 of which were the flavonoids. There were 9 differential compounds between the refreshing and orchid-like XYMJ teas, 6 of which were the L-amino acids and their derivatives. KEGG metabolic pathway enrichment analysis showed that the differential compounds were significantly enriched in the pathways of alanine, tyrosine and tryptophan biosynthesis, and flavonoids biosynthesis. L-valine, L-isoleucine and L-leucine were found to show significantly different among the XYMJ teas with different aroma types, which contributed importantly to the XYMJ tea aroma formation. Understanding the differences of non-volatile compounds among the XYMJ teas with different aroma types had important implications for promoting the precious processing technology of XYMJ teas.
