Milk Protein Coatings Prevent Oxidative Browning of Apples and Potatoes

Abstract

ABSTRACT Color analysis on apple and potato slices coated with calcium caseinate or whey protein solutions showed that the 2 coatings efficiently delayed browning by acting as oxygen barriers. The antioxidant properties of the films were realized using a model allowing the release of oxidative species by electrolysis of saline buffer. Whey proteins were a better antioxidant capacity than calcium caseinate. Furthermore, addition of carboxymethyl cellulose (CMC) to the formulations significantly improved their antioxidative power. Best scavenging of oxygen free radicals and reactive oxygen species was found for films based on whey proteins and CMC which inhibited by 75% the formation of colored compounds produced by the reaction of the oxidative species with N,N‐diethyl‐ p ‐phenylenediamine.