Process Optimization for the Production of Bio-functional Whey Protein Hydrolysates: Adopting Response Surface Methodology.

Abstract

Whey is a protein complex derived from milk, exhibit highest protein quality rating among other proteins, being touted as a functional food with number of health benefits. In the present investigation, whey proteins hydrolysates produced using trypsin enzyme to augment antioxidant activity and to assess angiotensin converting enzyme (ACE) inhibition activity. Hydrolysis parameters were standardized applying response surface methodology. The response antioxidant activity in terms of Trolox equivalent antioxidant capacity (TEAC) values was determined by radical scavenging assay method. Optimum conditions for maximum antioxidant activity were standardized at 88 °C of preheating, 7.3 pH, 0.05 enzymes to substrate ratio and hydrolysis was carried up to 8 h at 36.5 °C. Resulting peptide fractions obtained at 11.8 % of degree of hydrolysis displayed antioxidant capacity with TEAC values of 1.37 ± 0.12. The designed model found to be significant with R2 value of 0.9972 for antioxidant activity and lack of fit test-as non significant, indicating that the optimized conditions were best suited. The hydrolysate further investigated for antihypertensive activity. The outcome indicate that to affect decrease in ACE inhibition activity 4,166.72 μg of native whey protein is required when compared to 229.96 μg of hydrolysates. These results indicate hydrolysate produced under these conditions could be an effective nutraceutical.