Efficient reduction of β-lactoglobulin allergenicity in milk using Clostridium tyrobutyricum Z816
Qianru Zhao, Yuwei Wang, Zhengming Zhu, Quanyu Zhao, Liying Zhu, Ling Jiang
Abstract
Milk allergy is one of the most common food allergies, affecting 6 % of young children, and β-lactoglobulin (β-LG) is the main milk allergen. Clostridium tyrobutyricum Z816 was selected for the degradation of β-LG, which was successfully reduced by about 90 % using permeabilized bacteria under the optimized conditions. The hydrolyzed peptides were identified by liquid chromatography-tandem mass spectrometry (LC-MS/MS) and analyzed by molecular modeling, which indicated that C. tyrobutyricum Z816 could effectively degrade the antigenic epitopes of β-LG. Finally, the concentration and digestibility of β-LG in actual samples was quantified using enzyme-linked immunosorbent assay (ELISA) and gastrointestinal digestion simulation experiments. The results showed more than 92 % of β-LG in actual samples was hydrolyzed, and the gastric and total digestibility of whey protein isolate (WPI) was improved by 85.96 % and 64.51 %, respectively. Therefore, C. tyrobutyricum Z816 offers an effective method to degrade β-LG and reduce the occurrence of milk allergies, which has great significance for the development of hypoallergenic dairy products.