Comparative studies on antioxidant activity of buffalo and cow milk casein and their hydrolysates

Abstract

This study presents the antioxidant activity of buffalo milk casein and its hydrolysates and their comparison with cows' milk casein. 2, 2' azinobis (3-ethylbenzthiazoline-6-sulphonic acid) (ABTS) decolourization assay was used to evaluate the antioxidant activity of different casein fractions (α s -, β- and κ-casein), their peptic and corolase PP hydrolysates and corresponding (3k Da cut off) ultrafiltration (UF) permeates. The relative order of antioxidant activity was observed to be α S - > β- > κ-casein and the antioxidant activity of buffalo milk casein and its fractions was higher than corresponding cow milk casein and its fractions. Hydrolysis with corolase PP resulted in greater increase in antioxidant activity as compared to pepsin and the increase in antioxidant activity with individual protease was to similar extent irrespective of type of casein fraction from buffalo and cow milk casein (P<0.05). The 3kDa UF-permeates mainly represented the total antioxidant activity of hydrolysates.