Nontargeted and targeted metabolomics analysis for evaluating the effect of ?golden flora? amount on the sensory quality, metabolites, and the alpha-amylase and lipase inhibitory activities of Fu brick tea

To investigate the effects of golden flora amount on the sensory quality, metabolites and bioactivities of Fu brick tea (FBT), FBT samples with different golden flora amounts were prepared from the same materials by adjusting the water content before pressing. With the increase of golden flora in samples, the tea liquor color changed from yellow to orange red and the astringent taste gradually diminished. Targeted analysis demon-strated that (-)-epigallocatechin gallate, (-)-epicatechin gallate, and most amino acids gradually decreased as the increase of golden flora. Seventy differential metabolites were identified by untargeted analysis. Among them, sixteen compounds including two Fuzhuanins and four EPSFs were positively correlated with golden flora amount (P < 0.05). The FBT samples with golden flora exhibited significantly higher inhibitory potency on alpha-amylase and lipase than the samples without golden flora. Our results provide a theoretical basis of guiding FBT processing based on desired sensory quality and metabolites.

Automated summary

This study investigated the effects of golden flora amount on the sensory quality, metabolites, and bioactivities of Fu brick tea. Different golden flora amounts were used to prepare the tea samples, resulting in changes in tea liquor color and astringent taste. Targeted analysis revealed decreased levels of (-)-epigallocatechin gallate, (-)-epicatechin gallate, and most amino acids with increased golden flora. Untargeted analysis identified 70 differential metabolites, where 16 compounds, including two Fuzhuanins and four EPSFs, were positively correlated with golden flora amount. Fu brick tea samples with golden flora demonstrated higher inhibitory potency on alpha-amylase and lipase. These findings provide a theoretical basis for guiding the processing of Fu brick tea based on desired sensory quality and metabolites.