Changing Regularity Of Soy Allergenic Proteins During Soy Sauce Brewing And Soybean Germination

Soy sauce is made of soybean or soybean meal as main raw material,supplemented with starchy materials such as wheat and bran.The liquid seasoning with rich flavors is prepared through five processing stages of boiling,koji making,fermentation,oil pouring and sterilization.Various studies have shown that soy sauce have low soybean's allergenicity,and the brewing process of soy sauce involves multiple food processing processes,which have different effects on the degradation of soybean allergens.Therefore,this paper studies the degradation rules of soybean protein allergens during the brewing of low-salt solid state and high-salt dilute soy sauce.soybean germination can effectively improve the nutritional structure of soybean and reduce the allergenicity of soybean protein.Soybean germination can effectively improve the nutritional structure of soybeans and reduce the allergenicity of soy protein.This article also studied the changes of soybean allergens and anti-nutrition factor urease activity during the germination of soybeans,in order to look for suitable production of hypoallergenic soy raw materials.SDS-PAGE,ELISA and immunoblotting combined immunological methods were used to evaluate the sensitization of soybean allergenic proteins during the brewing process of low-salt solid soy sauce,high-salt dilute soy sauce and soybean germination.Soy protein was extracted from soybeans and New Zealand white rabbits were immunized by soy protein to obtain rabbit anti-soybean polyclonal antibody,and then the polyclonal antibodies were evaluated.Based on the establishment of a simulated low-salt solid soy sauce brewing laboratory,the samples of untreated soybean,autoclaved?121?C,8 min?,samples with koji making time of 14,27,36 and 44 h,Samples fermented for 5?10?17?24 and30 d?pre-sterilization and sterilization were taken.Samples of high salt dilute soy sauce were obtained from a soy sauce factory in Shandong.Soybeans,samples after cooking,samples for 30 hours during the koji making phase,fermentation liquids of 15,20,28,36,and 44 days were taken from the fermentation phase.Raw soy sauce sterilized sample and prepared sample.The composition of proteins in the brewing process was measured by polyacrylamide gel electrophoresis,and rabbit anti-soy polyclonal antibodies were used to perform enzyme-linked immunoassay and immunoblot experiments to analyze the changes in soybean allergen antigenicity during fermentation.Soybean samples were germinated at 20?C for 7 days,and germinated samples were taken daily.The sensitization and antigenicity of allergen proteins during soybean germination were analyzed by immunoblotting and indirect competitive enzyme-linked immunosorbent assay.Urease activity was measured by GB/T 8622-2006 method.The results are summaried as follows:1.Compared with the raw material soybean,the antigenicity in the sample decreased by 8.13%,39.00%,69.10%,and 87.06%after high-pressure cooking,koji making,fermentation,and heat sterilization,respectively,the allergenicity decreased by 8.92%,71.66%,92.26%,and 98.45%,respectively.After 30 days of fermentation,glycinin can still be detected in raw soy sauce,and was not completely degraded after sterilization,but these residual soybean allergens did not show IgE binding capacity.The allergenicity and antigenicity of soybean allergens gradually decreased during the low-salt solid-state brewing process.2.During the process of cooking,koji making,fermentation,sterilization,and blending of high salt dilute soy sauce,the antigenicity of soybean allergens was reduced by 30.32%,47.05%,43.55%,59.66%,and 54.87%,respectively.The koji-making stage has the greatest influence on the degradation of soybean allergens during the soy sauce brewing process.Sterilization and filtration also play an important role in removing allergens in soy sauce.3.The changes of bean sprout antigenicity and allergenicity showed a trend of decreasing first and then increasing during the germination process.Soybean antigenicity was reduced by 24.56%and allergenicity was reduced by 30.00%after 1^th of germination.The soluble protein loss at this time was only 6.90%compared with ungerminated soybean.Soybean allergen content method.The antigenicity of bean sprout root decreased by 80.00%after 4^th germination.Gly m Bd 30 K was the main allergen in the bean sprout root.The allergenicity of soybean sprouts was reduced by 54%and the antigenicity was reduced by 44%.Urease activity decreased by 67%after 5^thh germination.When soybean sprouts are about 6 cm in length,their allergen content and urease activity are low,which is suitable for the development of soybean sprouts that are easy to absorb and have low sensitivity.