Effects of ultrasound-assisted immersion freezing on the muscle quality and physicochemical properties of chicken breast

•Ultrasound immersion freezing (UF) enhanced the freezing rate of chicken breast.•The appropriate ultrasonic power reduced the ice crystal size in chicken breast.•UF at 165 W (UF-165) reduced the thawing and cooking loss of chicken breast.•UF-165 samples maintained the highest chicken breast protein thermal stability.•UF-165 samples had less mobility and loss of immobilized water and free water. This paper evaluated the impact of air freezing (AF), immersion freezing (IF) and ultrasound-assisted immersion freezing (UF) at different power levels (125, 165, 205 and 245 W) on the muscle quality and physicochemical properties of chicken breast. As the ultrasonic power increased, the total freezing time of the UF samples first decreased and then increased. UF at 165 W (UF-165) remarkably shortened the freezing time of the samples. Microstructure analysis showed that UF-165 samples had the smaller and more uniform ice crystals. In addition, UF-165 effectively reduced the thawing and cooking losses (P