Effect Of Electron Beam Irradition On The Structure And Functional Properties Of Egg White Protein

Egg white powder（EWP）contains high-quality protein,whichcan be modified to develop a high-quality special protein powder to increase its added value.Electron beam irradiation（EBI）,a new type of food sterilization and mutagenesis technology,produces high-energy electron beam rays in a short period of time.EBI pretreatment directly or indirectly on the EWP will result in the changes of protein structure and functional properties.In this paper,it is investegated the effects of EBI pretreatment with different doses on the structure and functional properties of EWP.The findings will provide a basis for the development of EWP products in future.The major results are as follows:1.The effects of EBI doses（0,5,10,20,30,50,70 and 100 k Gy）on the EWP structure were studied.When EBI doses are less than 70 k Gy,the charged groups of the irradiated EWP is easily transferring to the molecular surface,the intermolecular force of the protein is constantly changing,and the-SH content increase.However,the effect of EBI pretreatment on secondary structure compositions is not significant.2.The effects of EBI doses（0,5,10,20,30,50,70 and 100 k Gy）on the solubility（biurea method）,antioxidant properties（ABTS radical scavenging capacities）and emulsification characteristics（soybean oil emulsification）of EWP were performed in this work.A conclusion has been drawn that the irradiated EWP shows higher solubility and emulsification activity than the untreated sample,and the ABTS radical scavenging activity of the irradiated EWP is improved to a certain extent.All these experimental results are higher than those reported in the literature.3.The effects of EBI doses（0,5,10,20,30,50,70 and 100 k Gy）on the in vitro digestion rate of EWP were studied.It indicates that the in vitro digestibility of the irradiated EWP was improved,and the in vitro digestibility of EWP irradiated at 100 k Gy was high up to 99.3±0.53%.After the digestion treatment of the irradiated EWP,the protein digestion solution shows high Fe²⁺chelating capacity and the OH radical scavenging activity,Also the protein digestion solution has good ABTS radical scavenging activity with high level of more than 80%.