Preparation and Allergenicity Assessment of Hypoallergenic Hydrolyzed Whey Powder

Whey protein, the main allergen of bovine milk, was treated by alkaline protease enzymatic hydrolysis process to explore the changes of its allergenicity, and compared with two types of commercially available hypoallergenic whey powders. Bovine whey protein was spray dried after enzymatic hydrolysis, and the allergenicity of the enzymatic hydrolysate and its residual epitope information were evaluated by enzyme linked immunosorbent assay and liquid chromatography tandem mass spectrometry. The intestinal transport rate, molecular weight distribution, hydrolysis degree, sensory characteristics and other indexes were evaluated by Ussing Chamber system, gel electrophoresis, electronic tongue and other methods. The results showed that the molecular weight of hypoallergenic hydrolyzed whey powder was significantly reduced after treatment by alkaline protease enzymatic hydrolysis process. Mass spectrometry analysis of residual epitopes showed that all epitopes of α-lactalbumin in hypoallergenic hydrolyzed whey powder were enzymatically hydrolyzed, while several epitope residues of β-lactoglobulin were still undamaged, among which AA17-33 existed in different degrees of hydrolyzed whey powder samples. According to the serum pool detection of patients with milk allergy, the allergenicity of hypoallergenic hydrolyzed whey powder was lower than that of commercially available partially hydrolyzed whey powder under similar degree of hydrolysis. The results of Ussing Chamber showed that the intestinal transport rate of hypoallergenic hydrolyzed whey powder was good, similar to that of commercially available extensively hydrolyzed whey powder, while the bitterness was weaker and more palatable than that of commercially available extensively hydrolyzed whey powder. In summary, the treatment of whey protein by alkaline protease enzymatic hydrolysis process could significantly reduce the allergenicity of the product, enhance product had good transport and absorption capacity, and reduce the bitter taste, which had good application potential and development prospects.