Improved effect of ultrasound-assisted enzymolysis on egg yolk powder: Structural properties, hydration properties and stability characteristics

•Egg yolk powder with high solubility and excellent dispersion stability was prepared.•The yolk proteins sonicated at 60 W for 20 min had the highest degree of hydrolysis.•Ultrasound-assisted enzymolysis led to smaller particle size of yolk particles.•Ultrasound treatment enhanced the hydrogen bonding forces between proteins.