NUTRITIONAL-VALUE AND ANTIGENICITY OF 2 MILK PROTEIN HYDROLYSATES IN RATS AND GUINEA-PIGS

Two milk protein (whey protein and casein) hydrolysates were obtained by enzymatic hydrolysis. In the casein hydrolysate, an ultrafiltration stage was performed to remove all the peptides with molecular weights >2500. A nutritional value study of both hydrolysates was undertaken. No differences were found between the native proteins and their enzym atic hydrolysates. Neither the enzymatic hydrolysis nor the heat treat ments used affected the nutritional value of the protein sources. The two hydrolysates were studied for antigenic properties. The enzymatic hydrolysis of the whey protein concentrate followed by a thermal treat ment at 90 degrees C for 10 min reduced significantly its antigenicity . However, the in vivo allergenicity tests showed some positive reacti ons in both systemic anaphylaxis and passive cutaneous anaphylaxis. Th e casein hydrolysate, after being ultrafiltered, was devoid of sensiti zing capacity by the oral route and was also ineffective in producing local or systemic anaphylaxis in previously sensitized animals, as sho wn by in vivo assays.