Comparison of thawing assisted by low-intensity ultrasound on technological properties of pork Longissimus dorsi muscle

The objective of the present study was to analyses technological and textural properties of pork thawed by low intensity ultrasound compared to meat thawed conventionally in air (control) or by immersion in water. The pork thawing was done by means of a generator of constant frequency, with adjusting ultrasound intensity, coupled with a transducer plate and a water bath. The frequency of 25 kHz and the intensity of 0.6 W/cm2 allowed reducing by 87 % the time required for thawing from -5 degrees C to -1 degrees C as well as the overall thawing time as compared to thawing in air. Using intensity of 0.2, 0.4, and 0.6 W/cm(2) thawing rates were 0.62, 0.73, 1 degrees C/min, versus 0.16 degrees C/min in the control. The textural and technological properties of meat thawed by ultrasound are not impaired by the significant lowering of thawing time; there were no large mass loss or modification of meat ultrastructure as compared to control.