Effect of different doses of Co-60 gamma-ray irradiation treatment on the micro-rheological and emulsifying properties of liquid egg white

Abstract

This study investigated the effects of different irradiation doses (0kGy, 1kGy, 3kGy, 5kGy) on the structural and emulsifying properties of egg white protein by studying the egg white protein emulsion particle size, zeta potential, emulsion droplet microstructure, emulsification index, interfacial tension, secondary structure, micro-rheological properties. The results show that after irradiation treatment, the average particle size of the emulsion was significantly (p < 0.05) reduced, and the zeta potential value was significantly (p < 0.05) increased. As the irradiation dose increased, the interfacial tension between the oil phase and the water phase decreased, and the two-phase separation time of the emulsion is significantly (p < 0.05) prolonged. The content of α-helix and β-sheet of the protein was significantly (p < 0.05) decreased, while the content of β-turn and random coil was significant (p < 0.05) increased. In the microstructure of the emulsion droplets, the dispersion of the emulsion droplets after irradiation was improved, and the observed droplet size was significantly reduced. In terms of rheological properties, the fluidity of the egg white protein emulsion droplets increased. The elasticity and viscosity of the egg white protein emulsion decreased. All these results suggested that irradiation treatment can improve the emulsification characteristics and stability of egg white protein.