This study optimised the conditions for ultrasound-assisted extraction (UAE) of defatted wheat germ protein (WGP) and evaluated its effect on functional properties. Single-factor orthogonal experiment designs were combined to optimise UAE condition. The WGP reached highest level, at 88.66%, with a solid : liquid ratio 1 : 25 g·mL–1, pH value 9.0, ultrasonic time 10 min, power 400 W. U...