Effect of Cladosporium tenuissimum on the metabolic profile and the quality of Liupao tea during aging process

The purpose of this research is to accelerate the aging of Liupao tea by inoculating it with Cladosporium tenuissimum . Results revealed that the liquor color, aroma, and taste of the FT group (Liupao tea inoculated with C. tenuissimum for aging fermentation) were greatly improved. The contents of galloyl catechins in the FT group decreased dramatically from 5.827 mg/g to 4.507 mg/g ( p <0.05), however, the contents of theabrownins increased significantly, rising from 75.090 mg/g to 118.540 mg/g ( p <0.01), which considerably weakened the bitterness and astringency while improving the sweet-mellow flavor of Liupao tea, and caused the liquor color to change from orange-red to red-brown. The volatile compounds were significantly different between the FT group and the control group (Liupao tea without being inoculated with C. tenuissimum ), which improved the aroma from a stale aroma to a sweet-grassy aroma. Metabolomic analysis revealed that the volatile precursors were the major differential metabolites. In summary, inoculation of C. tenuissimum for fermentation can greatly impact the metabolic profile and improve the quality of Liupao tea by accelerating the aging process. • Cladosporium tenuissimum were used to rapid aging technology on Liupao tea. • C.tenuissimum inoculation enhanced Liupao tea's sensory quality and stage efficiency. • Metabolomics showed C. tenuissimum strongly affected tea’s volatile precursors.