Temperature effect on the non-volatile compounds of Maillard reaction products derived from xylose-soybean peptide system: Further insights into thermal degradation and cross-linking

摘要

Solutions of soybean peptide with or without xylose were heated over a range of temperatures (80-130℃) for 2 h to investigate the characteristics of Maillard reaction and the effect of temperature on amino acids and peptides. It was found that both peptide degradation and peptide cross-linking occurred in the Maillard reaction. The critical temperature for peptide degradation was 100 ℃, and above it, peptides degraded quickly in thermal degradation system. However, in Maillard reaction system, peptides cross-linked rapidly when the temperature reached 110 ℃. Bitter amino acids and peptides below 1000 Da decreased 18.44% and 28.49%, respectively, after Maillard reaction at 120 ℃. On the other hand, peptides between 1000 and 5000 Da were increased significantly, nearly doubled compared to its initial hydrolysates after Maillard reaction at 120 ℃. Moreover, the increase of macromolecule products was also accompanied with severe browning and pH decrement.