Influence of Enzymatic Hydrolysis on the Nutritional, Functional and Antioxidant Properties of Protein Hydrolysates Prepared from Seinat (Cucumis melo var. tibish) Seeds

The effect of enzymatic hydrolysis time on nutritional, functional properties and antioxidant activities of seinat seed protein isolates were studied. Hydrolysates of seinat seed protein isolates (HSSPIs) were prepared at different time (30-180 min), using two food-grade proteases. Trypsin was applied in the first hydrolysis stage followed by Pepsin. The hydrolysis time showed significant differences (p<0.05) on nutritional parameters such as essential amino acid score, essential amino acid index, biological value and predicted protein efficiency ratios. All the functional properties studied decreased as hydrolysis time increases. Antioxidant activities; (DPPH radical scavenging, ABTS radical scavenging and ferrous chelating) of HSSPIs increased with increase in hydrolysis time. Large amounts of small-sized peptides (3,000-5,000 Da) were observed with decreased as hydrolysis time increased (2.07-1.28%). The results in this study indicated that increase in hydrolysis time has positively affected nutritional and antioxidant properties of HSSPIs, but had a negative impact on the functional properties studied.