Flavor and metabolite responses of Ganoderma lucidum to different drying methods: integrated electronic sensing, volatilomics, and metabolomics analysis.

This study systematically investigated the effects of four drying methods, freeze vacuum drying (FD), microwave vacuum drying (MVD), hot air drying (HD), and natural drying (ND), on the flavor profile and metabolite composition of Ganoderma lucidum (G. lucidum). FD appears to best preserve natural color, thermolabile flavor compounds, and bioactive constituents, resulting in a flavor profile most similar to that of fresh samples. HD significantly altered the profile of volatile compounds, and the marked increase in 5'-IMP likely contributed to the enhanced umami intensity. Integrated correlation analysis and weighted gene co-expression network analysis suggest that 1-nonen-3-one and 1-octen-3-ol may be key volatiles driving odor differences among treatments. Nitrogen-containing heterocycles and triterpenoids were associated with bitterness, whereas 5'-IMP, specific amino acids and derivatives were the main contributors to umami. These findings demonstrate how drying methods differentially shape G. lucidum flavor through coordinated modulation of volatile and non-volatile metabolite networks.