以围网捕获的新鲜鲣鱼为原料,研究了船上冷盐水浸渍快速冻结(1.40 cm/h)和慢速冻结(0.46 cm/h)的传热传质及其对鱼体冻结和储藏品质的影响。结果表明:快速冻结的传热速度快,鲣鱼快速和慢速冻结所需冻结时间分别为9 h和24 h:快速冻结的鲣鱼在冻结后和储藏期间的盐分吸收量显著低于慢速冻结(P<0.05)。同时快速冻结鲣鱼的TVB-N增长缓慢,储藏至第28天时未超过20 mg/100g;pH值、TBA值和高铁肌红蛋白相对百分含量值的增长也显著小于慢速冻结(P<0.05)。鲣鱼颜色、气味和质地的感官评分结果也显示出快速冻结鲣鱼较好的感官品质。冷盐水快速冻结有利于保持鲣鱼冻品品质。

Skipjack was used as raw material in this study,the differences of heat-mass transfer and quality changes between fast-freezing( 1. 40 cm / h) and slow-freezing( 0. 46 cm / h) in cold brine onboard was invesigated. The results revealed that the freezing time needed for fast-freezing and slow-freezing were 9 hours and 24 hours,respectively. The salt uptake of skipjack by fast-freezing process was significantly slower( P < 0. 05) than slow-freezing. During early freezing stage and storage time,TVB-N value of skipjack by fast-freezing increased slowly and failed to exceed 20 mg /100g after 28 days of storage. Meanwhile,Changes of pH value,TBA value,metmyoglobin percentage of skipjack by fast-freezing were significantly slower( P < 0. 05) than these by slow-freezing process,which was in accordance with the sensory results on color,flavor and texture of skipjack. Therefore,fast-freezing in cold brine had advantages on preservation of skipjack onboard.