Antioxidant effects of protein hydrolysates in the reaction with glucose

Maillard reaction products (MRP) obtained by reaction between glucose and protein hydrolysates from casein and fish were investigated. The influence of parameters such as reaction time and glucose concentration was studied. The antioxidative activity of MRP was determined by using the beta-carotene/linoleate model and the 1,1-diphenyl-2-picrylhydrazyl method. All experiments showed that the antioxidative effect was improved by 20-30% when the hydrolysates were reached with glucose. A dramatic increase in antiradical efficiency of the MRP (up to 75%) was also observed. The study of the chromatographic profiles obtained before and after the Maillard reaction found changes in absorbance at 280 nm, indicating molecular rearrangements that could be involved in the improvement of the antioxidative and free radical-scavenging activities.