• Development and Reproduction
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• v.16 no.2
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• pp.77-85
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• 2012

Various cryoprotective agents (CPA) were tested to establish the best conditions for the cryopreservation of sperm from black porgy Acanthopagrus schlegeli acclimated and raised in freshwater (BFW). Survival rates of frozen/thawed sperm from BFW were higher in the order of dimethy sulfoxide (DMSO), glycerol, ethylene glycol (EG) and methanol. Sperm motility was higher in the order of glycerol, DMSO, EG and methanol. These effects were the same in thawed sperm from black porgy raised in seawater (BSW). Thus, optimum CPA for sperm cryopreservation of BFW and BSW were DMSO and glycerol where the highest survival rates and sperm motility were found at the concentration of 10%. In particular, the survival rates and motility of thawed sperm from BFW and BSW after cryopreservation using 10% DMSO were better than when cryopreserved using 10% glycerol. On the other hand, for the thawed sperm from both BFW and BSW, the longer the preservation period was, the lower the survival rates and sperm motility were. Notably, the higher the concentration of CPA was, the lower the survival rates and sperm motility were.

• Journal of the Korean Society of Food Science and Nutrition
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• v.19 no.2
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• pp.175-179
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• 1990

Investigations of skin stripping freezing and thawing conditions of common-European squid (Loigo vulgaris) were carried out. The most effective method of skin stripping was to immerse the sample at 5$0^{\circ}C$ for 10-15 minutes in fresh water or salt solution(5-10% w/v) Contact freezing and fresh water thawing method was found to be effective. The muscle structure of the sample thawed after contact freezing was almost the sample after contact freezing was almost the same as that of raw sample.

• Journal of the Korean Home Economics Association
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• v.35 no.2
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• pp.147-157
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• 1997

It attempted to determine the effect of various thawing methods, such as pressure cooking, conventional cooking, microwave heating and thawing at room temperature, on the quality of frozen cooked rice using Nongan variety of rice. These effects were analysed at three different periods-after 10 days, 30 days and 90 days. It conducted a physico-chemical analysis(moisture content, dehydration rates, color value and texture) and sensory evaluation o the frozen-thawed cooked rice. The study showed that there were no significant differences on the frozen-thawed cooked rice. The study showed that there were no significant differences on the quality characteristics of frozen-thawed cooked rice during the storage of 90 days. However, the thawing method of pressure cooking caused high moisture content and decrease in hardness on the cooked rice, the desirability for the rice didn't diminish compared with the cooked rice just after cooking. the quality characteristics of the cooked rice after frozen-thawing by conventional cooking and microwave heating were similar with that of the cooked rice just after cooking. thawing at room temperature caused a significant decrease in quality characteristics.

• Journal of Aquaculture
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• v.12 no.1
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• pp.1-5
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• 1999

To obtain fundamental data for sperm cryopreservation in river puffer (Takifugu obscurus), the proper conditions of cryopreservation were investigated. In the sperm cryopreservation of river puffer, marine fish Rinser's solution (MFRS) was found to be good diluent and dimethyl sulfoxide (DMSO) was proved to be superior to glycerol as a cryoprotectant. The highest fertilization rate was achieved when river puffer sperms were cryopreserved with MFRS adding 5％ DMSO.

• Journal of the Korean Society of Food Science and Nutrition
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• v.29 no.1
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• pp.15-19
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• 2000

Physicochemical properties of frozen immatured soybean (Miwon) under various thawing conditions were investigated. The moisture content, density and other chemical compositions were not affected by the thawing conditions. Thelightness of soybean and soybean hull decreased when thawing with 1$0^{\circ}C$ water while it increased when other thawing conditions used. Hardness and vitamin C content decreased with all thawing conditions ; especially decrease in vitamin C content was severe with microwave thawing. Lipoxygenase activity was significantly decreased when thawing with microwave and 1$0^{\circ}C$ water. It was recommended that thawing with 1$0^{\circ}C$ water was the most apropriate method in terms of overall quality.

• Journal of the Korean Society of Food Science and Nutrition
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• v.43 no.12
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• pp.1906-1912
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• 2014

To evaluate the effect of freezing temperature on quality of blueberries, blueberry fruit was frozen at -20, -45, and $-70^{\circ}C$ immediately after harvest. After 24 hr of freezing, frozen blueberries were stored at $-20^{\circ}C$ for 2 months. Blueberries were thawed at $4^{\circ}C$ or $25^{\circ}C$ and subjected to subsequent analyses of drip ratio, fruit hardness, pH of juice, color, and sugar content. Frozen berries at all three temperatures did not show any significant difference in pH or sugar content compared with fresh berries. The drip ratio of berries decreased as the freezing temperature decreased. Thawing conditions significantly affected the drip ratio of berries frozen at $-20^{\circ}C$. Hardness of berries was significantly reduced after freeze-thawing. Freezing and thawing reduced total aerobic bacteria and yeast/mold numbers by more than 2 log regardless of freezing or thawing temperature ($4^{\circ}C$ or $25^{\circ}C$). Cross-section of blueberries did not show different shapes by freezing temperature. Further studies such as sensory evaluation are needed to determine the optimum freezing temperature regarding quality and cost.

• Journal of the Korean Society of Food Science and Nutrition
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• v.41 no.2
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• pp.246-253
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• 2012

In this study, we determined the optimum blanching conditions for pretreatment of Aster scaber prior to freezing to ensure its long, safe preservation as a fine cooking ingredient. Frozen-thawed A. scaber did not significantly differ between blanching groups, but the blanched group showed significantly higher Hunter L, a, and b values than the un-blanched group (p<0.05). Higher temperatures and longer treatment times increased softness; hardness did not significantly differ between the blanched and un-blanched groups of frozen-thawed A. scaber (p<0.05). Total bacterial counts and the presence of coliforms seemed to decline with blanching treatments, but treatment temperature and time did not influence this reduction. Over 95% of peroxidase activity was inactivated by blanching treatment but increased slightly after thawing. The sensory evaluation of the frozen-thawed A. scaber by test group showed the A. scaber blanched at $90^{\circ}C$ for 3 min to be the most highly preferred (p<0.05).

• Korean Journal of Fisheries and Aquatic Sciences
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• v.8 no.1
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• pp.37-45
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• 1975

The present study was ,conducted to evaluate the effects of condensed phosphates on the refeezing damage of Alaska pollack muscle. The fillets were dipped in such solution as 5 and $10\%$ sodium polyphosphate, 1 and $5\%$ mixture of sodium polyphosphate and sodium pyrophosphate (1:1, w/w) for 1 and 5 minutes, respectively, before refreezing. And fillets were frozen at $27^{\circ}C\~28^{\circ}C$ and stored for 15 days at $-18^{\circ}\~-20^{\circ}$. The degree of denaturation was estimated by determining amounts of drip relased, content of total solids, nitrogen, and DNA in the drip an cooking-weight-loss. Phosphorus absorbed in the muscle was also determined. Phosphorus absorbed in the fillets treated with loft solution of sodium polyphosphate for 5 minutes amounted to 101 mg/100g muscle as $P_2O_5$. The absorption was dependent on tile concentration of treating solution rather than on the dipping time. The increase of phosphorus absorption seemed to affect to reduction of drip. Among the treating conditions, $10\%$, 5 minutes and $10\%$ 1 minute with sodium polyphosphate appeared most effective ones on drip reduction. The effect of $5\%$, minutes with the mixture of sodium polyphosphate and sodium pyrophosphate did not show so benefitable effect in refrozen fillets. As a tendency total solids, nitrogen, and DNA in tile drip varied proportionally to the amount of drip released. And the content of DNA was lower than the amount. Treatment, at higher the concentration and longer the dipping time, resulted in the lower cooking-weight-loss and the better quality on organoleptic test of thawed fillets.

• Journal of fish pathology
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• v.22 no.2
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• pp.167-172
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• 2009

Antibody-detection enzyme-linked immunosorbent assay (ELISA) was performed to determine whether the absorbance value of ELISA is influenced by the different serum storage conditions of olive flounder Paralichthys olivaceus. Flounder antiserum to bovine serum albumin was stored at -80, -20, 4 and 20${^{\circ}C}$ for 1, 30, 69 and 124 days, respectively. In addition, the flounder antisera were frozen at -80 and -20${^{\circ}C}$, respectively and then repeated 1, 5 and 10 thaw-freeze cycles. No significant difference was shown in ELISA optical density (O.D.) values of sera, which were stored at the above mentioned storage conditions during 124 days. ELISA O.D. values of unfrozen serum samples, which were previously stored at 4${^{\circ}C}$, were almost similar to those of sera undergoing 1, 5, and 10 freeze-thaw cycles after stored at -80 or -20${^{\circ}C}$. In conclusion, the ELISA O.D. values of flounder sera were not affected by various storage conditions: different temperatures (-80, -20, 4 and 20${^{\circ}C}$), durations of storage (1, 30, 69 and 124 days), and repeated thaw-freeze cycles (1, 5, and 10 times).

• Proceedings of the Korean Nuclear Society Conference
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• 1995.05b
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• pp.609-615
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• 1995

Chip machining에 의한 U$_3$Si 분말제조시 절삭가공조건이 분말 입도 분포에 미치는 영향을 조사하기 위하여 U$_3$Si ingot를 선반에서 초경공구를 사용하여 절삭속도 및 이송속도를 변화시키면서 chip을 가공하였고, 가공된 chip의 형상을 광학현미경으로 관찰하고 칩의 크기를 측정하였다. 모든 절삭조건에서 톱니모양의 칩(saw toothed chip)이 형성되었으며, 일정한 절삭속도에서 공구의 이송속도를 변화시켰을 때 이송속도가 증가함에 따라 칩 두께의 증가와 함께 chip segment의 폭도 증가하여 chip segment 의 크기가 뚜렷이 증가함을 보였다. 또한 chip segment의 크기는 절삭속도 보다는 공구의 이송속도에 크게 영향을 받는 것을 알 수 있었고 분말의 입도 분포에도 크게 영향을 미치는 것으로 나타났다.