Effects of Maillard Reaction on the Flavor Characteristics of Enzymatic Hydrolysates of Panus giganteus

To investigate the effects of the Maillard reaction on the flavor characteristics of enzymatic hydrolysates of Panus giganteus, this study used the L-cysteine tracing method combined with single-factorial and orthogonal experiments to optimize the preparation process of Maillard reaction products (MRPs). The changes in flavor profiles before and after reaction were analyzed using high-performance liquid chromatography (HPLC), electronic nose, electronic tongue, molecular weight distribution analysis, and sensory evaluation. The results showed that the optimal two-stage preparation conditions for MRPs were as follows: The initial stage was set at 3% xylose addition, 60 min reaction time, 50 ℃ reaction temperature, and an initial pH of 7.5; The second stage involved 0.8% L-cysteine addition with a subsequent reaction at 110 ℃ for 80 min. MRPs prepared under these conditions had a sensory score of 76.3 with no formation of excessive browning substances. Instrumental analysis results demonstrated that hydrolysates after the Maillard reaction exhibited a significant decrease in total free amino acids, TAV and EUC, alongside an increased content of umami 5'-nucleotides, a higher overall sensory score, and an 18.25% reduction in the relative proportion of peptide fractions <1 kDa. Furthermore, the Maillard reaction results of enzymatically hydrolyzed peptides from different molecular weight P. giganteus indicated, the Maillard reaction products obtained from the enzymatically hydrolyzed peptides of <1 kD had a lighter color, lower browning degree, and less melanoidin formation. In summary, the Maillard reaction effectively improves the flavor profiles of P. giganteus enzymatic hydrolysates, which provides a theoretical basis for the deep processing of P. giganteus resources and their application in the food industry.