Abstract:The vacuum decompression method can significantly shorten the processing period of preserved eggs, but the mechanism of gelatin formation of egg white gel under this technology is unknown. Thus, in this paper, to explore the gel formation mechanism, water migration in egg white, protein conformational change, microstructure and intermolecular force changes were investigated, during the gelatinization process of egg white of preserved egg using the vacuum decompression method. Results showed that, during the pickling process of preserved egg, the hydrophobicity of egg white protein first increased and then decreased, the proper hydrophobic interaction was helpful to maintain the stability of the protein gel structure. The turbidity of egg white protein was significantly increased while the solubility was significantly reduced, the Zeta potential was increased by 1.13 times, the increase in electrostatic repulsion was beneficial to the formation of ordered linear protein aggregates, forming a transparent gel; the relative content of α-helical was reduced to 13.00%, while the β-sheet and β-turn structure were increased to 54.00% and 20.40%, respectively, the α-helix structure is transformed into β-structures to participate in the aggregation between protein molecules; the intermolecular forces that maintain protein gels in order from strong to weak were ionic bonds, disulfide bonds, hydrophobic interactions, and relatively few hydrogen bonding; through the above interactions, preserved egg whites finally formed a regular three-dimensional fiber network gel structure embedded with a large amount of bound water.
