Heating and cysteine effect on physicochemical and flavor properties of soybean peptide Maillard reaction products.

Abstract Maillard reaction products (MRPs) were obtained by using the xylose and soybean peptide system through a 2 h heating at pH of 7.6. Cysteine addition and thermal treatment at 80, 100, 120 and 140 °C were investigated via E-nose and E-tongue, free amino acids (FAA) and GC–MS analyses of MRPs. Afterwards, the combined effects were performed using the partial least square regression (PLSR). Results suggested that MRPs without cysteine addition (XSs) had stronger browning intensity, and the cysteine would be beneficial to the pH reduction with heating temperature increasing. PLSR analysis revealed that MRPs with cysteine addition heated at 140 °C (XSC-140) showed the lowest bitterness, and XS-100 had the highest umami and saltiness. Both bitter and umami FAA increased with the addition of cysteine, and more furans and nitrogen-containing compounds formed in the XSs brought caramel-like flavor, while XSCs exhibited meat-like flavor attributed to sulphides generation. Highlights • Maillard reaction products with or without cys were got at various temperatures. • High temperature promoted the formation of browning products and volatiles. • Cysteine addition reduced the formation of color, bitterness, umami and saltiness. • Higher umami and saltiness could be obtained at 100 °C heating without cysteine. • Lower bitter but meaty flavor could be obtained at 140 °C heating with cysteine. [ABSTRACT FROM AUTHOR]