Effects Of Different Processing Methods On Major Allergen Of Chinese Mitten Crab,Eriocheir Sinensis

Food allergy is a special type of foodbom disease,which has obtained widespread attention globally.Crustacean is one of the eight major sources of food allergens proposed by the Food and Agriculture Organization.Chinese mitten crab(Eriocheir sinensis),also called river crab,was one of the most important aquaculture species in China.Generally speaking,it is widely loved by consumers due to its delicious taste and rich nutrition.Recently,with the increasing production and consumption of river crab,the high rate of consumption has led to increased allergy problems.It influences the eating safety of river crab and the health of people.According to the research,tropomyosin(TM)has been proved to be the main allergen of river crab.Nowadays,domestic and foreign researches on river crab TM are mostly focused on extraction,purification and immunology.Therefore,it is of great significance to study different processing methods that can reduce the allergenicity of river crabs.This study used river crab(Eriocheir sinensis)as material.First,TM was purified from river crab meat by isoelectric point precipitation and ammonium sulfate salting–out.The pure allergen protein was analysised and identificatied by sodium dodecyl sulfate–polyacrylamide gel electrophoresis(SDS–PAGE)and western–blotting.Then,different processing methods(such as steaming,back pressure cooking,high temperature and pressure,microwave,high pressure processing,ultrasonic and ultrasonic assist steaming)were adopted to treat river crab meat.Standard simulated gastric fluid(SGF)and standard simulated intestinal fluid(SIF)were applied to explore the digestibilities of tropomyosin with various processing methods.Then,the digestive stability and allergenicity of TM after being processed were analyzed by SDS–PAGE,western blotting and inhibition ELISA.The results showed that different processing methods could affect the digestibility of TM,among the processing methods,high temperature and pressure treatment,back pressure cooking treatment,ultrasound and ultrasonic assist steaming treatment could enhance the degradation of TM in the digestion,the allergenicity of TM and its degraded fragments were reduced either(P<0.05).In summary,this study focused on exploring the processing characteristics of crab TM,indicating that high temperature and pressure,ultrasound,ultrasonic assist steaming and back pressure cooking could promote the digestion and degradation ofTM,and reduce its allergenicity.These results are expected to provide an important theoretical basis for the in–depth study of the allergen properties of Chinese mitten crabs and the development of hypoallergenic aquatic foods.