Improving the flavor of protein hydrolysates from shrimp processing byproducts via maillard reaction: Towards structure-flavor relationship.

This study aimed to improve the flavor of protein hydrolysates from shrimp byproducts by Maillard reaction. The structural and flavor characteristics of Maillard reaction products from shrimp byproducts were analyzed. Glucosamine and xylose demonstrated superior reactivity. The free amino group content of xylose-induced Maillard reaction significantly decreased to 188.37 mmol/L after 60 min, while the grafting degree reached the highest value (24.35 %). The UV absorbance of xylose- and glucosamine-induced Maillard reactions significantly increased at 294 and 320 nm, while the browning index remained low. E-nose and GC-MS/MS confirmed higher levels of pyrazines and benzaldehyde in xylose-induced samples. E-tongue analysis revealed that xylose- and glucosamine-induced Maillard reactions significantly enhanced the saltiness (13.78 %, 12.01 %) and umami (10.81 %, 11.45 %), while also reducing bitterness. LC-MS/MS indicated glycopeptides implicated in formation of umami peptides and pyrazines. Overall, glucosamine and xylose improved flavor with xylose generating more aromatic compounds and glucosamine enhancing umami and salt taste.