• The Korean Journal of Food And Nutrition
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• v.18 no.3
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• pp.168-174
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• 2005

Various changes of physico-chemical characteristics of chilled plaice muscle during storage at $4^{\circ}C$ in vacuum and aerobic packaging methods were examined. As a storaging period become longer, Hunter L, a, b value changes slightely. However, no differences were observed between vacuum and aerobic packaging method. The hardness of plaice muscle after death was $2,232\;dyne/cm^2$. The hardness of vacuum packaged plaice muscle storaged for 4 days was similar to that of aerobic packaged plaice muscle storaged fur 14 days. MFI(Myofibrillar Fragmentation Index) of aerobic and vacuum packaged plaice muscle showed maximum value at storage for 4days and 7 days, respectively. Mg-ATPase activities of mypofibril were increased gradually both of all during storage days. But that of MF from aerobic packaging plaice muscle was higher than that of vacuum packaging plaice muscle.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.18 no.5
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• pp.455-463
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• 1985

Thermal-denaturation of myofibrillar protein of dorsal skeletal muscle from file fish was investigated by measuring denaturation constant($K_D$) and thermodynamic parameters at various temperatures. The protective effects of sucrose, sorbitol and amino acids when added individually or combined were also discussed. The denaturation rate as reflected in inactivation of myofibrillar protein Ca-ATPase was followed the first order reaction. The $K_D$ values at $25^{\circ}C,\;30^{\circ}C,\;and\;35^{\circ}C$ were $19.52{\times}10^{-5},\;112.25{\times}10^{-5},\;and\;247.20{\times}10^{-5}$, respectively. The activation energy of the reaction at $30^{\circ}C$ was 43 kcal/mole. The protective effects of sucrose, sorbitol, glycine, alanine and Na-glutamate were increased with the concentration but the effects of sorbitol and Na-glutamate decreased beyond 1.0 mole. Basic amino acids such as arginine and lysine did not revealed any protective effect on the thermal denaturation. In case of mixed addition, the effects of Na-glutamate to glycine, sorbitol to glycine, and sorbitol to sucrose or sorbitol to Na-glutamate were enhanced 1.2 to 7.0 times as much as that of control (ratio of mixing; 1:1, range of concentration; 0.5 to 1.25 mole). Under the frozen condition at $-20^{\circ}C$, two mixtures such as Na-glutamate to glycine and sorbitol to sucrose apparently revealed the protective effects.

• Korean Journal of Food Science and Technology
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• v.25 no.5
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• pp.468-474
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• 1993

A dehydrating sheet comprises polymeric water absorber. which are packed in a semipermeable cellophane film bag allowing selective permeation of water. This sheet dehydration is quite different from conventional drying method such as sun drying, hot-air blast drying and cold air blast drying in a sense that samples are dried without heat treatment. As a part of the studies to develope a new processing method for effective utilization of dark muscle fishes, the preparation of a good quality salted and semi-dried mackerel by the dehydrating sheet was attempted. The dehydration time for preparation of a salted and semi-dried mackerels containing approximately equal moisture content were revealed $180{\sim}510min$ in conventional drying method and $90{\sim}160min$ in this sheet dehydration, respectively. The moisture and histamine contents of those salted and semi-dried mackerels were $59.4{\sim}62.4%$ and $2.5{\sim}3.6 mg/100g$, respectively. The changes in peroxide value, fatty acid composition, brown pigment formation, myofibrillar protein solubility and Ca-ATPase activity during processing of the salted and semi-dried mackerel prepared by the sheet dehydration were more lower than those of products prepared by conventional drying methods. Therefore, these result showed that the quality of a salted and semi-dried mackerel prepared by the sheet dehydration was imperial to that of those products by conventional drying method.