Food Chemical Study on Cultured Fish.

这项研究是为了比较野生鱼和养殖鱼的肌肉成分及其在储存过程中的变化。结果表明：(1)养殖黄尾鱼骨骼肌在贮藏过程中K值的增加率高于野生黄尾鱼，提示K值增加率与肌肉脂肪含量之间可能存在一定的相关性；(2)野生黄尾鱼肌肉脂中α-生育酚含量高于养殖黄尾鱼，野生鱼贮藏过程中α-生育酚下降幅度较大。(3)养殖黄尾鱼肌肉中的TBA值高于野生黄尾鱼。黄尾肌的TBA值与肌脂中α-生育酚含量呈负相关(r=-0.86)。养殖鱼类在贮藏过程中TBA值增加的速率较大，黄尾鱼通常摄食沙丁鱼作为饲料，但养殖黄尾鱼饲料的沙丁鱼应在发生脂质过氧化反应时进行长时间的冷冻保存。因此，在养殖黄鱼和野生黄鱼之间观察到的这些肌肉成分的差异似乎是所摄取的饲料的脂质过氧化程度不同的结果。如上所述，黄鱼的保质期。以K值和TBA值作为新鲜度指标，取决于肌肉中脂肪和d-生育酚的水平，因此，可以认为养殖黄尾鱼的货架期应随饲料性质的不同而波动。

This study was undertaken to compare muscle components and their changes during storage among wild-- and cultured-fish. Results obtained are summarized as follows :(1)The increasing rate of K-value of skeletal muscle during storage was higher in cultured-yellowtail than in wild-one, and it is suggested that there may be some correlation between the increasing rate of K-value and lipid content of muscle.(2)Concentration of alpha-tocopherol in muscle lipid was higher in wild-Yellowtail than in cultured one, and the decreasing rate of alpha-tocopherol during storage was larger in wild-fish.(3)In muscle of cultured-Yellowtail, TBA-value was higher than in wild one. The TBA value of yellowtail muscle was inversely relative(r = - 0.86)to the concentration of alpha-toccopherol in muscle lipid. The increasing rate of TBA-value during storage was larger in cultured fish.Yellowtail usually intakes sardine as a feed, but the sardine, on which cultured--Yellowtail feeds, should have been subject to prolonged frozen storage, when lipid peroxidation reactions proceeds. Then, these defference of muscle constituents observed between cultured- and wild-yellowtailseem to be the result of the difference in degree of lipid peroxidation of the feed intaken. As mentioned above, the shelf life of yellowtaii. judged by K-value and TBA-value as the freshness index, depended upon the levels of lipid and d-tocopherol in muscle, therefore, it is reasonable to assume that the shelf life of cultured--Yellowtail should fluctuate depending upon the properties of feed.