Gelation Enhancement of Soy Protein Isolate using the Maillard Reaction and High Temperatures

Abstract
Soy protein isolate gels prepared by autoclaving solutions in the presence of xylose of glucono‐δ‐lactone (GDL), were compared. In both cases, the pH decreased from neutral to pH 5.5 during gel formation. In the xylose systems, this pH decrease was a consequence of the Maillard reaction. The Maillard gels showed less syneresis, had a higher breaking force and were more elastic, as determined by stress relaxation, then the GDL gels. The differences were attributed to formation of additional covalent crosslinks due to the Maillard reaction, as evidenced by greatly reduced solubility in sodium dodecyl sulfate +β‐mercaptoethanol.