Metabolomic analysis provides insights into the mechanism of color and taste changes in Dictyophora indusiata fruiting bodies under different drying processes

In this study, we systematically assessed how the morphology and texture of edible fruiting bodies of D. indusiata (EFD) varied under three drying techniques: vacuum freeze drying (FD), vacuum drying (VD), and hot air drying (HD). It was discovered that freeze-dried EFD samples (FD-EFD) had an intact microstructure, and thus, a good appearance, textural characteristics, and rehydration properties. Quantitative metabolomic analysis revealed 801 metabolites, where 236 211 metabolites were significantly different in abundance in the comparison of hot-air dried EFD samples (HD-EFD) versus FD-EFD and vacuum-dried EFD samples (VD-EFD) versus FD-EFD, respectively. VD and HD significantly affected the abundance of taste-related compounds and resulted in the improvement of EFD's umami. The acidity of EFD is provided by organic acids produced through the tricarboxylic acid cycle. The browning of HD-EFD was caused by Maillard reactions, oxidative degradation of ascorbic acid, and endogenous enzymatic browning process dominated by the phenylalanine metabolic pathway. The metabolomic analysis provides new insights into changes in EFD by different drying processes.

Automated summary

In this study, the effects of three drying techniques on the morphology and texture of edible fruiting bodies of D. indusiata (EFD) were systematically assessed. Metabolomic analysis revealed significant changes in the abundance of metabolites in EFD samples dried using different techniques. Freeze drying preserved the microstructure of EFD samples and improved their appearance, texture, and rehydration properties. Vacuum drying and hot air drying influenced the abundance of taste-related compounds and enhanced the umami of EFD. The browning of hot air dried EFD was caused by Maillard reactions, oxidative degradation of ascorbic acid, and phenylalanine metabolic pathway.