Phosphorylation altered structural flexibility of goose liver protein: Relation to interfacial and emulsifying properties

Abstract

This work elucidated the roles of ultrasonication (GLP-U), phosphorylation (GLP-S) and their combination (GLP-US) on the emulsifying properties of goose liver protein (GLP-N) from an interfacial perspective. Results of interfacial pressure (11.98 ± 0.24 mN/m) and elastic modulus (10.63 ± 0.12 mN/m) showed that combined ultrasonication and phosphorylation rendered the highest interfacial interaction of GLP-N by facilitating its structural flexibility. Microrheology and multiple light scattering indicated that the enhanced electrostatic repulsion among GLP-US favored the interdroplet dissociation. Consequently, both the droplet size and flocculation index of emulsions were markedly decreased using either low (19.53 μm ± 1.06 and 8.18%) or high particle concentration (7.75 ± 0.24 μm and 6.85%) of GLP-US when compared with the sole treated groups and the control. Overall, phosphorylation fortified the intradroplet protein-protein interaction but restrained the interdroplet interaction of GLP-N, and the assistance of ultrasonication endowed the protein with enhanced interfacial stabilization and emulsifying efficiency.