Formation of key aroma compounds in Agrocybe aegerita during hot air drying: Amino acids and reducing sugars identified as flavor precursors.

Agrocybe aegerita is a type of mushroom widely popular among consumers for its unique flavor. In this study, aroma properties and key aroma-active compounds (AACs) in fresh and dried A. aegerita were identified by molecular sensory science. The flavor characteristics are more abundant in A. aegerita submitted to hot air drying (HAD), especially nutty, roasted, smoky and meaty, while raw mushroom and earthy were significantly reduced, which can be attributed to the shift of key AACs from aldehydes and ketones to heterocyclic and sulfur-containing compounds during HAD. Pearson correlation analysis and validation experiments showed that the Maillard reaction between methionine (Met) and ribose was the main pathway for producing "meaty" compounds like dimethyl trisulfide and 3-methylthiopropanal. Moreover, dimethyl trisulfide and 3-methylthiopropanal production showed a nonlinear fit with increasing Met and ribose contents. The study provides a theoretical basis for A. aegerita as a novel meat flavor condiment.