不同方式冻结后养殖大黄鱼肌肉理化特性在冻藏期间的变化

Physico-chemical properties changes during the frozen storage of farmed Pseudosciaena crocea muscle after freezing by different methods

采用高压转换冷冻法(PSF法)和常规空气冷冻法(CAF法)冷冻大黄鱼,并在-20℃下储藏3个月。结果表明,CAF法生成的冰晶大而少,肌纤维严重收缩和变形,相反PSF法生成的冰晶少而多,分布均匀,对肌纤维的破坏程度小,且205MPa下冰晶更小。3个月后PSF冷冻的样品组织显微结构均没有明显改变;PSF法冷冻的样品在冻藏期间盐溶性蛋白含量均没有显著变化(p>0.05),而CAF法冷冻的样品在冻藏期间盐溶性蛋白含量显著减少(p<0.05);较之CAF,PSF法冷冻的样品弹性和咀嚼性均显著提高(p<0.05)。因此,PSF法在大黄鱼保鲜方面具有潜在的应用前景。

Farmed Pseudosciaena croceas were frozen either by pressure shift freezing （PSF） or by conventional air freezing （CAF）,and then stored at -20~C for 3 months. Results showed that .. firstly , large and little ice crystals were formed during the CAF process and then irreversiable damage to muscle fibres were formed. On the other hand,smaller and more regular intracellular ice crystals were observed in samples frozen by PSF, especially during the PSF（205MPa） process. Secondly,these frozen by PSF didn＇t experience significant changes during the frozen storage,such as microstructure and the salt extractable protein. In the case of CAF muscle,content of salt extractable protein decreased significantly（p〈0.05） during the frozen storage. Thirdly, springiness and chewiness of the muscle were improved significantly after freezing by PSF（p〈0.05）. Therefore, PSF could serve as a promising technique for commercial quality enhancement of Pseudosciaena croceas.