Water‐Thawing of Fish Using Low Frequency Acoustics

Blocks of Pacific cod (plate frozen; 91‐mm thickness and 12.7 kg) were thawed in an 18°C circulated water bath and simultaneously exposed to 1500 Hz acoustic energy not exceeding 60 watts. A ceramic transducer was positioned for light contact with a frozen block. A motorized belt moved the block in order to distribute the 239 cm 2 transducer over the 1500 cm 2 block surface. At 60 watts continuous input to the transducer, the block thawed in 71% less time than water‐only controls. Quality analyses indicated that the flesh was not adversely affected by the acoustic waves.