Insight into ultrasound-assisted phosphorylation on the structural and emulsifying properties of goose liver protein

The aim of this study was to elucidate the effect of ultrasound-assisted phosphorylation on the structural and emulsifying properties of goose liver protein (GLP), and GLP underwent different treatments (native (GLP-N), only ultrasound (UGLP), only phosphorylation (GLP-STP) and ultrasound-assisted phosphorylation (UGLP-STP)). UGLP-STP showed the highest phosphorylation degree of GLP among four groups; The FT-IR spectrum confirmed the phosphate group covalently attached to GLP in UGLP-STP. The highest hydrophobic capability and solubility were exhibited in UGLP-STP, resulting from the transformation of α-helix and β-turn into β-sheet and random coil. The treatment of UGLP-STP showed significantly higher values in emulsifying activity (32.24 ± 0.27 m²/g) and emulsifying stability (103.59 ± 2.40%) compared with other treatments. Confocal laser scanning microscopy suggested that UGLP-STP showed largest uniformity of particle distribution and smallest size than other groups. These results implied that ultrasonic-assisted phosphorylation showed a great improvement in emulsifying properties of goose liver protein.