Insight into the mechanism of the quality improvement of porcine after ultrasound-assisted immersion freezing

The influences of ultrasound-assisted immersion freezing (UIF) at different power density levels (15, 30, 45 W L-1) on the quality characteristics of porcine M. longissimus lumborum were evaluated. The results showed that UIF was effective in inhibiting juice loss, enhancing tenderness along with colour stability of porcine, especially at UIF of 30 W L-1 (UIF-30). This improvement induced by UIF was attributed to the rapid freezing rate, the reduction of freezable water content, the formation of tiny and even ice crystals and the maintenance of muscle fibre integrity. This study indicated UIF with appropriate density (UIF-30) and was beneficial to improve the quality of pork muscle to the greatest extent.