Fig. 4: Aroma compound detection and analysis in YCFSs.

a Category and quantity of volatile compounds for all samples. b The ratio of aroma compounds. c OPLS-DA score plot of aroma compounds in YCFSs from different seasons. d PLS-DA score plot of aroma compounds in YCFSs from different grades. e Venn diagram of the main aroma compounds (VIP > 1) distinguishing YCFS by season and grade. f Heat map of aroma compounds (VIP > 1, p < 0.05) distinguishing YCFS by season and grade.