• Journal of Embryo Transfer
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• v.14 no.2
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• pp.131-137
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• 1999

This experiment was carried out to investigate the effects of osmolarity of thawing diluents, seminal plasma added in thawing diluents on the sperm viability and the effects of thawing temperature, the temparature of the thawing diluents on the sperm viability and acrosomal morphology of boar spermatozoa by the straw method. The result obtained were summarized as follows: 1. The sperm viablilty after thawing of the frozen semen was shown greater in the high osmolarity(392~492mOsm) than low osmolarity(300mOsm) in thawing diluent. The added levels of seminal plasma in thawing diluent did not affect the viability of frozen-thawed boar semen. 2. In terms of thawing temperature, the sperm viability was shown higher in the frozen semen thawed at 5$0^{\circ}C$ for one min. (p<0.01) than those thawed at 2$0^{\circ}C$ or 37$^{\circ}C$ for one min. The sperm viability was not significant at the diluent temparature of 2$0^{\circ}C$or 37$^{\circ}C$ after thawing: but the sperm viability was higher in thawing diluent at 2$0^{\circ}C$ than in that at 37$^{\circ}C$. However, the effects of thawing temperature and diluent solution on normal acrosomal rate were not significant. 3. Cleavage rates of oocytes fertilized with frozen semen were 46.4% and 43.3%, respectively, which were thawed at 5$0^{\circ}C$ for one min. and then diluted in mBTS medium at 2$0^{\circ}C$or 37$^{\circ}C$. To sum up, the sperm viability was shown greater at the high of thawing diluents of frozen boar semen. In terms of thawing conditions, the sperm viability was shown greater, when semen was thawed at a high temperature for a short time and then diluted at the same temperature as that in the straw.

• Journal of Advanced Marine Engineering and Technology
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• v.27 no.2
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• pp.280-288
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• 2003

We need refrigeration system which can maintain the freshness of agricultural products, because of being distance from a tiller to a consumer. Vacuum Pre-cooling system has an advantage in quality maintenance through vapid cooling down by using latent heat of evaporation of stored products. A number or thawing methods in current use have also several disadvantages in thawing time. discoloration mass loss caused by drying, capital costs and running cost. These damages are, it is claimed, either eliminated or improved by the vacuum thawing system. An experimental study on the pre-cooling for the bean sprouts and cabbage, and thawing for hairtail and croaker by the low temperature vacuum system were carried out. The cabbage cooling time with this Pre-cooling vacuum system took about 60 minutes to reach from $23.2^{circ}C to 4.5^{\circ}C$ at 5 mmHg abs. ($6.66\times10^{-4}$ MPa). The croaker thawing time with this low temperature vacuum thawing system took about 170 minutes to reach from $-10.3^{circ}C to -0.8^{\circ}C$ at 20 mmHg abs ($2.67\tiems10^{-3}$MPa). The vacuum Pre-cooling and thawing system have merits compared with present systems in their short intervals to cool down and to thaw without any quality losses.

• Korean Journal of Animal Reproduction
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• v.21 no.3
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• pp.287-292
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• 1997

This study was carried out to investigate the effects of concentration and kinds of cryoprotectants, equilibraction time, thawing temperature and time, sucrose concentration on the survival rates of frozen bovine demi-embryos. The bovine demi-embryos following dehydration by cryoprotectants a various concentration of sucrose were freezed by cell freezer and thawed in 3$0^{\circ}C$ water bath. Survival and in vitro developmental rates was defined as development rates on in vitro culture or FDA-test. The results are summarized as follows : 1. The high survival rates of demi-embryos after frozen-thawing in freezing medium was attained 2.0M glycerol. The high survival rates of demi-embryos after frozen-thawing in freezing medium was obtained using single cryoprotectant(25.0~30.0%) than mixed cryoprotectants(16.7~19.0%). 2. The survival rates of demi-embryos after frozen-thawing in freezing medium added 1.5M, 2.0M glycerol＋0.25M sucrose(37.5~33.3%) were higher survival rates than those of sucrose concentration of 0.50, 0.75M(12.5~26.7%). 3. The equilibration time on the survival rates of demi-embryos was attained after short period of time(30.0~35.0%) in the freezing medium higher than long period of time(21.1%). 4. The thawing temperature on the survival rates of demi-embryos was attained at 3$0^{\circ}C$ of thawing temperature(26.7~40.0%) higher than $25^{\circ}C$ or 37$^{\circ}C$ of thawing temperature(13.3~20.0%). 5. The thawing time on the survival rates of demi-embryos was attained at 1~5 minutes of thawing time(26.7~33.3%) in the freezing medium higher than 10 minutes of thawing time(13.3~18.8%).

• Journal of Fisheries and Marine Sciences Education
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• v.28 no.4
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• pp.1152-1158
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• 2016

This study was used samples, mackerel (Scomber japonicas), Japanese Spanish mackerel (Scomberomorus niphonius), alaska pollock (Theragra chalcogramma), yellow croaker (larimichthys crocea) known as some of the major species fisheries products in Korea We were investigated temperature change during thawing processing, water holding capacity, drip loss, extractive-nitrogen and viable cell count by various thawing methods, thawing at the room temperature (TRT), hot-air thawing (HAT), aeration thawing (AT), high-frequency thawing (HFT). The temperature changes have taken 2~3 hours in HFT and 24 hours by TRT. The expressible drip loss was 0.47~0.87 g/100 g in HFT, 1.91~4.42 g/100g in TRT, 1.31~4.93 g/100g in HAT, and 2.01~4.59 g/100g in AE. The water holding capacity was higher samples thawing by HFT than other thawing methods. Extractive-nitrogen was 276~452 mg/100 g in HFT, 177.21~420.27 mg/100 g in TRT. Viable cell count was $10^2$ to $10^3$ in HFT, $10^3$ to $10^5$ in other thawing methods. The processing speed and uniformity by HFT was minimized the risk of product degradations (drip losses, deterioration of sensorial, chemical and physical characteristics, bacteria growth, etc.), thus helping to preserve at its best the product quality than those by thawing methods. Therefore, HFT was expected to make high-quality thawing products anticipate future thawing technology

• Food Science of Animal Resources
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• v.34 no.1
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• pp.115-121
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• 2014

This study explored the effects of water or brine (2% NaCl, w/v) immersion thawing combined with ultrasound treatment (40 kHz, 150 W) on the quality characteristics of pork. Ultrasound treatment of pork was conducted in two cold media (at $4^{\circ}C$), water and 2% (w/v) brine, respectively. Because the ultrasound treatment caused temperature increase in the media from $4^{\circ}C$ to $16^{\circ}C$, the qualities of pork thawed by ultrasound were compared with those thawed by immersion either in water or brine where the temperature was being maintained at either $4^{\circ}C$ (low temperature control) or $17^{\circ}C$ (high temperature control). The ultrasound treatment resulted in rapid thawing of pork where the thawing rate was similar to those thawed in the $17^{\circ}C$ media. For quality characteristics, ultrasound-treated pork in brine had an advantage of less cooking losses when comparing to the control. In particular, ultrasound treatment in brine exhibited the lowest shear force (or highest tenderness) among the freezing/thawing treatments. Although the ultrasound processing in brine caused discoloration of the pork, this thawing technique had potential to be applied as a commercial thawing technology for frozen foods.

• Culinary science and hospitality research
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• v.14 no.2
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• pp.286-292
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• 2008

The purpose of this study was to examine the effects of freezing and thawing methods on the quality of pork meat. The freezing methods for pork meat were the cryogenic freezing with liquid nitrogen gas, fast freezing at $-70^{\circ}C$ and normal freezing at $-20^{\circ}C$. The thawing methods were tested on low temperature thawing at refrigerative temperature($4^{\circ}C$), room temperature($20^{\circ}C$), high temperature($60^{\circ}C$) and using microwave. The quality of pork meat frozen by cryogenic methods was better than those of fast and normal freezing methods. The cooking hardness of pork meat frozen by cryogenic method showed the highest value as 1,898 g. In case of fast freezing, the hardness of pork meat was 1,472 g and that of normal frozen pork meat was 1,541 g. The high cooking hardness value of cryogenic frozen pork meat showed that the cryogenic freezing method made less freeze damage like textural softness. The drip-loss of pork meat thawed at refrigerative temperature($4^{\circ}C$), room temperature($20^{\circ}C$), high temperature($60^{\circ}C$) were shown lower than that of microwave thawing. The cooking hardness of pork meat that was thawed by microwave showed the lowest value among the thawing methods. The cryogenic freezing was the most useful freezing method for preserving quality, decreasing the freeze damage of pork meat. And thawing at refrigerative temperature was the most effective method to prevent quality loss and weight loss by drip-loss.

• Korean Journal of Food Science and Technology
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• v.22 no.2
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• pp.123-128
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• 1990

In order to establish the optimal thawing condition of frozen fork, hot-air thawing and microwave thawing were evaluated at various conditions. In hot-air thawing, the higher the air temperature and the lower the meat surface temperature, the grater the thawing rate was. In microwave thawing, the grater the power and the lower the meat core temperature, the faster the thawing rate was. Comparing the two methods, microwave thawing was found to be significantly faster than hot-air thawing. TBA value and cooking loss were higher in hot-air thawing than that of refrigeration thawing or microwave thawing. Total extractable protein tended to be lower in hot-air thawing than that of the other two thawing methods. WHC decreased with the increase of hot-air and meat surface temperature whereas no significant difference was observed in microwave thawing regardless of the thawing conditions. Total microbial counts of thawed meat by the hot-air or microwave thawing were lower than that of refrigeration thawing.

• The Korean Journal of Food And Nutrition
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• v.16 no.4
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• pp.359-364
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• 2003

Frozen doughs for danish pastries were made by straight dough method to study the effect of thawing temperature on the quality of pastries. Danish pastry doughs were immediately frozen at -40 $^{\circ}C$ quickly after make-up and stored for 6 weeks at -20$^{\circ}C$ and baked after thawing and fermentation a week. Thawing temperature and fermentation time were controled to 3 hr at 5$^{\circ}C$, 2 hr at 10$^{\circ}C$, and 1.5 hr at 20$^{\circ}C$, respectively. The number of survival yeast cells in dough and the volume, the moisture content, the texture of danish pastries were investigated. Survival yeast cells showed the highest number at thawing temperature of 5 $^{\circ}C$. The volume of danish pastries decreased significantly according to the increase of frozen storage time and danish pastries thawed at 5$^{\circ}C$ revealed the largest volume. In moisture contents of danish pastry, there was no significantly difference without regard to the thawing temperature but showed the highest moisture content at thawing temperature of 20$^{\circ}C$. Danish pastries thawed at 5$^{\circ}C$ accomplished the best texture in the resulting pastry.

• Food Science of Animal Resources
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• v.34 no.6
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• pp.777-783
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• 2014

This study investigated the effect of various freezing and thawing techniques on the quality of beef. Meat samples were frozen using natural convection freezing (NF), individual quick freezing (IQF), or cryogenic freezing (CF) techniques, followed by natural convection thawing (NCT) or running water thawing (RT). The meat was frozen until the core temperature reached $-12^{\circ}C$ and then stored at $-24^{\circ}C$, followed by thawing until the temperature reached $5^{\circ}C$. Quality parameters, such as the pH, water binding properties, CIE color, shear force, and microstructure of the beef were elucidated. Although the freezing and thawing combinations did not cause remarkable changes in the quality parameters, rapid freezing, in the order of CF, IQF, and NF, was found to minimize the quality deterioration. In the case of thawing methods, NCT was better than RT and the meat quality was influence on the thawing temperature rather than the thawing rate. Although the microstructure of the frozen beef exhibited an excessive loss of integrity after the freezing and thawing, it did not cause any remarkable change in the beef quality. Taken together, these results demonstrate that CF and NCT form the best combination for beef processing; however, IQF and NCT may have practical applications in the frozen food industry.

• Preventive Nutrition and Food Science
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• v.3 no.3
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• pp.234-240
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• 1998

This study attempted to determine the effect of various thawing methods and storage periods on the quality of froen cooked rice. Frozen cooked rice was thawed at four different methods, such as pressure cooking, conventional cooking, microwave heating and thawing at room temperature after 10 days, 30days and 90 days frozen storage. We conducted a physico-chemical analysis (moisture content, dehydration rates, degree of gelatinization, color value and texture) and sensory evalution 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 period of 90 days. However, the thawing method of pressure cooking caused high moisture content, rapid dehydration rates, and a high degree of gelatinization on the cooked rice. Thus, the desirabililty for the rice diminished becaused of the excess moisture content and the change of appearance and testure in the rice due to the high temperature. There were similiar quality characteristics to the cooked rice after forzen-thawing whether by conventional cooking or by microwave heating and just after cooking. Thawing at room temperature also caused a significant decrease in quality characteristics.