Abstract:To clarify the changes in egg quality and yolk protein structure during storage，fresh eggs were stored for 28 d with a temperature of（22±1） ℃ and relative humidity of 45%. The changes in egg freshness，physicochemical properties and processing characteristics of yolk protein during storage were investigated. It was found that with the prolongation of storage time（0-28 d），there was a significant decrease in the Haugh unit and yolk index of eggs and a continued deterioration in the quality of eggs. The carbonyl content of egg yolk protein increased significantly，but the total sulfhydryl content decreased significantly，indicating the ongoing oxidation reaction of egg yolk protein. During storage，the surface hydrophobicity of egg yolk protein went first up to 12.21 and then down to 7.23，with the secondary structure changing from order to disorder and the structure of egg yolk protein being destroyed. The emulsifying properties and foaming properties of egg yolk were optimal at 14 d and 21 d storage respectively and the effect of storage on the gel properties of egg yolk was not significant （p＞0.05）. In conclusion，storage leads to changes in the protein structure of egg yolk，which in turn changes the processing performance of egg yolk.