Comparison of non-volatile flavor compounds in Stropharia rugosoannulata soup processed by different methods

In this study, we investigated the non-volatile flavor compounds (5'-nucleotides, free amino acids, organic acids and soluble sugars) in Stropharia rugosoannulata soup under different processing treatments. S. rugosoannulata soups were first obtained from S. rugosoannulata powder of three different particle sizes under both thermal and non-thermal treatments. Then, the effects of processing methods on non-volatile compounds in these S. rugosoannulata soups were investigated. Specifically, the non-thermal treatment of high hydrostatic pressure (HHP) resulted in high levels of equivalent umami concentration (EUC, 827.44-1411.79 mg/100 g DM); ultrasonic treatment (UT) and homogenization (HG) led to high concentrations of soluble sugars (15.58-30.48 mg/g DM); while hot treatment (HT) contributed to high contents of total organic acids (65.52-98.39 mg/g DM). Besides, moderate fine grinding of S. rugosoannulata powder (P2) facilitated the release FAAs (free amino acids) and soluble sugars in the soup. These results suggested that HHP-P2 is beneficial to the preservation of non-volatile compounds in S. rugosoannulata soup. Our findings may improve the utilization of S. rugosoannulata in the soup industry.