• Journal of Power System Engineering
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• v.10 no.2
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• pp.62-67
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• 2006

The maintenance of continuity on food processing has created a need for the rapid reinstatement of many types of frozen fish to an ambient temperature and good condition. A number of thawing methods are in current use have also several disadvantages in thawing time. discoloration mass loss caused by drying, capital and running cost. These damages are, it is claimed, either eliminated or improves by the vacuum system. An experimental study on the thawing for hair tail and Yellow croaker by the vacuum system were carried out. The Yellow croaker thawing time with this vacuum system took out 170 minutes to reach from $-10.3^{\circ}C\;to\;-0.8^{\circ}C$ at 20mmHg abs. and hair tail thawing time 220 minutes to reach from $-12.2^{\circ}C\;to\;0^{\circ}C$ at 20mmHg abs.

• Korean Journal of Ichthyology
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• v.19 no.2
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• pp.173-177
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• 2007

A series of experiments were conducted to compare the effects of various diluents and cryoprotectants on the motility and survival rate in cryopreservation of the red seabream, Pagrus major sperm. Sperm was efficiently cryopreserved using 300 mM glucose as a diluent. Two cryoprotectant, dimethyl sulfoxide (DMSO) and glycerol, were added to 300 mM glucose to formulate the extenders at concentrations between 5% and 30% by volume for freezing. The highest post-thawed sperm motility and survival rate were obtained with 10% DMSO.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.11 no.2
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• pp.91-95
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• 1978

Histological changes of the abalone muscle occurring in the process of freezing as well as thawing were investigated, and its results were compared to the histological structure of fresh muscle. The muscles of the abalone were mainly composed of smooth muscle fibres, and its morphological structures is similar to those of the top shell. Mechanical damgage of the muscle fibres caused by freezing were not observed while a number of small ice crystals were found between the muscle fibres. The damage by thawing was not much remakable compare to the destruction of muscle fibres of fish.

• Korean Journal of Ichthyology
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• v.31 no.4
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• pp.195-200
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• 2019

An experiment was performed to obtain cryopreservation techniques of Pacific cod Gadus macrocephalus sperm. Milt were cryopreservation using five cryoprotectant demethyl sulfoxide (DMSO), ethylene glycol (EG), glycerol, methanol and propylene glycol (PG) with marine fish ringer's solution (MFRS) as diluent. Milt were cryopreserved each experimental methods like cryoprotectants (10% and 20%), equilibration time (3, 5 and 10 min) and freezing protocols (liquid nitrogen vapor above 3, 8 and 12 cm). Post-thaw sperm survival rate revealed the highest in 10% PG with optimum methods of equilibration time (3 min) and freezing protocol (liquid nitrogen vapor above 8 cm) about 21.3±1.8%. Hatching rate of fertilization eggs using fresh and cryopreserved sperm were no significantly different.

• Korean Journal of Ichthyology
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• v.23 no.1
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• pp.75-79
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• 2011

This study was conducted to investigate protocol standardization for cryopreservation spermatozoa of the bar-tailed flathead Platycephalus indicus. The suitability of the cryoprotectants, dimethyl sulphoxide (DMSO), glycerol and methanol were tested against three freezing rates and three thawing temperatures. DMSO and glycerol gave significantly higher motile index and survival rates than methanol. Among the freezing rates, freezing at a height of 2 cm above $LN_2$ surface for $10\;min^{-1}$ gave higher motile index and survival rates. In terms of best thawing temperature, $20^{\circ}C$ obtained the highest motility.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.6 no.3_4
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• pp.101-111
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• 1973

To study the effect of freezing rate on the duality of frozen abalone(Haliotis gigantea, GMELIN) liquid nitrogen spray freezing, air blast freezing, semi-air blast freezing, and still air freezing were carried out. The rheological change, protein denaturation, and free water content of frozen and thawed abalone were examined at the period of 0, 1, 2, and 3 month during cold Storage at $-20^{\circ}C$. The results are summarized as follows : 1. The onset and duration of rigor mortis of fresh abalone was faster and shorter as compared to that of fishes. 2. There was no difference in compression value and shear value between freezing methods but they varied with a slight decrease in storage period. 3. Gradual decrease in extractibility of salt soluble protein was observed in all samples except those frozen with liquid nitrogen. 4. The free water of the foot muscle remained constant during the storage while that of the adductor muscle tended to increase. 5. A significant correlation was observed among the changes of panel texture and free water (P< 0.01), protein denaturation (P<0.05), and compression value (P<0.01).

• Korean Journal of Food Science and Technology
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• v.29 no.4
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• pp.722-729
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• 1997

The study was undertaken to extend the shelf life of filleted and salted fishes such as mackerel and jacopever. These filleted and salted fishes were dehydrated by dewatering sheet containing sodium polyacrylate resin at $5{\pm}1^{\circ}C$, wrapped with low density polyethylene film, and then stored at $-18{\pm}2^{\circ}C$. During the frozen storage, the change of brown pigment formation, peroxide value, carbonyl value, drip formation content in the cold-osmotic dehydrated fishes after salt dipping were much lower than those of non-dehydrated ones. Moreover, the proteins and Ca-ATPase in the cold-osmotic dehydrated fishes after salt dipping were more stable than those of non-dehydrated ones during frozen storage. It was supposed that the cold-osmotic dehydration pretreatment processing for filleted and salted fishes was useful in improvement of the frozen storage stability.

• Journal of the Korean Society of Food Science and Nutrition
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• v.16 no.1
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• pp.36-41
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• 1987

In the refrigerated storages of fishery products, the lipid oxidation of the meats had been the major deterioration factor. For the effective utilization of mackerel, Scomber japonicus, and yellow corvenia, Pseudosciaena manchuria, which are major costal fish in Korea, and were studied about oxidative rancidity during the refrigerated storage at $-18^{\circ}C$ and the effect of different temperatures upon the cooked meat. We detected the results followed. 1. The Induction period of refrigerated storages had 20 days for fresh meat and 60 days for cooked meat. 2. Peroxide and TBA value of cooked meats had half amount values In the comparison with those of fresh meats, 3. Values of mackerel had double amount than those of yellow corvenia in peroxide and TBA value as if the different values come from different fish species, 4. The rancidative degree of the different temperatures on the samples had the least amount at $-5^{\circ}C$ among several kinds of storage temperatures.

• Analytical Science and Technology
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• v.11 no.1
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• pp.29-35
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• 1998

This study was performed to assess the levels of the Cr and Co in fisheries caught from the some areas of west coast in Korea. The samples were 26 kinds of fishes, 19 kindly of Mollusca and 3 kinds of Crustacea. They were ashed with 5 ml $HNO_3$ and then wet-decomposed with 10 ml of a mixture of $HNO_3:H_2SO_4:HClO_4$ (10:1:4). After ashing of samples, the amounts of Cr and Co in the samples were determined by ICP-AES analysis. The moisture content of molluscans was significantly higher than that of crustaceans (p<0.05), but there was no significant difference among fisheries in the Cr content. And the Co content of crustaceans was significantly higher than that of fishes and molluscans (p<0.001). There was no significance between contents of Cr and Co in fisheries. The Cr content of Arkshell was 422.00 ppm, which was the most amount compared with those of the other samples. And the Co in Myong-Ge was 3.78 ppm, which was the most amount. Areliscus honaleus (Cr:2.76 ppm, Co:0.97 ppm), Solen (Cr:6.56 ppm, Co:1.59 ppm) and dried barley shrimp (Cr:1.06 ppm, Co:0.90 ppm) contained great amount of Cr and Co.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.29 no.3
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• pp.309-319
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• 1996

Properties as related to the utilization of the crude proteases extracted from the muscle and viscera of fish (2 dark fleshed lish; anchovy, Engraulis japonica, and gizzard-shad, Clupanoda punctatus; 2 white fleshed fish; seabass, Lateolabrax japonicus, and sole, Pleuronichthys cornutus) were studied. Proteolytic activity of the muscle protease was slightly inhibited with the increase of sodium chloride concentration and it was apparent against the yellowtail myofibrillar protein than casein substrate. Proteolytic activities of the seabass and sole visceral crude protease were inhibited to 50 to $60\%\;by\;25\%$ of sodium chloride, but those of anchovy and gizzard-shad viscera crude enzymes were not influenced by sodium chloride. The vacuum freeze-dried crude protease and glycerol-mixed crude pretense of gizzard-shad and seabass muscles were almost lost their activities on the 16th week of storage, while those from the viscera of the fish were relatively stable. Degradation of the yellowtail myofibrillar protein by the anchovy muscle and viscera crude pretenses rapidly proceeded in the beginning of the reaction and the degraded products were mainly distributed in the range of 6 to 15 kDa electrophoretically.