• 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 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 the East Asian Society of Dietary Life
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• v.25 no.5
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• pp.893-901
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• 2015

This study investigated the effects of thawing conditions on physiological activities and quality of peeled garlic. Peeled frozen garlic was analyzed after thawing at low temperature ($4^{\circ}C$), room temperature ($20^{\circ}C$), tap water ($20^{\circ}C$), radio frequency of 27.12 MHz, and 2.45 GHz in a microwave. As a result, the time required to thaw garlic to $0^{\circ}C$ by various thawing methods was shortest at2.45 GHz in a microwave, followed by $20^{\circ}C$ tap water, radio frequency of 27.12 MHz, $20^{\circ}C$, and $4^{\circ}C$. Microwave thawing was faster than other methods, but it resulted in significant non-uniformity of heating. The hardness of peeled garlic significantly decreased upon freeze-thawing, whereas it showed improved hardness upon radio-frequency thawing. Total color difference in garlic increased upon freeze-thawing, and it was not improved by various thawing methods. Antioxidant activities were determined for DPPH radical scavenging ability, SOD-like activity, and reducing power. Total phenolic compounds and flavonoids in garlic extract were measured as $3.222{\pm}0.214{\mu}g$ GAE/g and $0.149{\pm}0.03{\mu}g$ QE/g, respectively. The content of total phenolic compounds was significantly reduced by 2.45 GHz microwave thawing ($1.90{\pm}0.02{\mu}g$ GAE/g); however, flavonoid contents were slightly reduced under freezing and thawing conditions. The DPPH radical scavenging ability of garlic extracts was not affected by thawing methods; however, SOD-like activity and reducing power were slightly reduced by freeze-thawing. These results indicate that physiological activities were not improved by radio-frequency thawing; however, thawing time and maintain hardness were reduced compared with conventional thawing methods.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.37 no.3
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• pp.175-178
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• 2004

We here report that the muscle of 'gukmeri-bok' puffer fish (Takifugu vermicularis radiatus) is intoxicated after freezing and thawing processes even though it is not toxic when it is fresh. This study was carried out to investigate the effect of different freezing and thawing conditions as well as the effect of the presence of skin or viscera on the intoxication of muscle of 'gukmeri-bok' puffer during freezing and thawing process. As a result of this investigation, thawing condition, but not freezing conditions or periods played an important role in muscle intoxication. Tetrodotoxin secretory grands exist in the skin of toxic puffer fish, the skin was more responsible for the muscles intoxication than the viscera during the freezing-thawing process. In other words, no toxicity was measured in the muscle of skinned-frozen specimens even when thawed. According to this result, it is recommended that the skin and viscera must be removed before being frozen for edible purpose. Otherwise, when a whole fish should be frozen, alternative half-thawing and removal of skin from frozen specimens is recommended.

• Proceedings of the Korean Society of Agricultural Engineers Conference
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• 2001.10a
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• pp.185-188
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• 2001

In this study, the characteristics of freezing and thawing resistance, the compressive strength, and the change in height of cement mortar according to a steam and taler curing conditions has been studied. To this end, the major test variables include the period of the early curing, curing temperature and the later curing. The strength test as well as volume variousness have been conducted to explore the characteristics of freezing and thawing resistance on the curing conditions. The experimental results can be efficiently used to improve the characteristics of freezing and thawing resistance for concrete products carrying steam curing.

• 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.

• Journal of the Korean Society of Food Culture
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• v.20 no.2
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• pp.253-260
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• 2005

This study was conducted to investigate performance of methods for cooking and thawing frozen cooked rice to retard retro-gradation of cooked rice. For this research, That was executed rice's physicochemical and sensory characteristics test through the way of boiling rice or thawing, and found out best way for retro-gradation and taste. This study showed the rice cooked by pressure rice pot has less dehydration during freezing and thawing, and thawed rice by micro wave has less dehydration. Repetition of freezing and thawing resulted increasing of hardness and chewiness, and decreasing of adhesiveness and cohesiveness. The rice cooked by convotherm oven or pressure rice pot has less increased hardness while freezing and thawing. Adhesiveness was superior when rice was cooked by pressure rice pot. The rice thawed by microwave had more hardness than thawed in room temperature.

• Food Science of Animal Resources
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• v.18 no.2
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• pp.142-148
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• 1998

This study was conducted to investigate the quality change of beef muscle, which was thawed by different thawing rate in order to utilize it as fundamental data for establishing optimal and thawing condition. Chilled beef round which was purchased at a commercial market was used. The samples were frozen for 30min(time required to pas through the maximal ice forming zone, -1$^{\circ}C$∼-7$^{\circ}C$) and the thawing conditions were 3.9cm/hr, 0.21cm/hr, 0.13cm/hr. Thawing losses of rapidly thawed meat(3.9cm/hr) were significantly(p＜0.05) lower(6.10%), but cooking and total losses were the highest as 48.17% and 56.44%, respectively(p＜0.05). Characteristics such as color, flavor, texture and overall quality at different the thawing rates showed similar scores, but slightly increased after storage for 24hr. Juiciness of rapidly thawed meat was significantly(p＜0.05) higher than that compared to the other thawing rates.

• Korean Journal of Agricultural Science
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• v.21 no.2
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• pp.133-141
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• 1994

Optimal thawing conditions of frozen model foods containing protein and starch were nvestigated at various thawing conditions such as room temperature, hot air, and microwave heating. Hardness of the frozen model foods was getting higher as the water content increased. Thawing rates at room temperature, hot-air heating at $50^{\circ}C$, and microwave heating were 0.02 Kg/min, 0.08 Kg/min, 0.01 Kg/min, respectively. Final thawing time was as follows; control 60min, 5% sucrose: 50 min, 10% sucrose: 30 min, 5% NaCl: 30 min. Total drip loss was as follows; room temperature thawing: 22.5%, 200W microwave thawing 1.3%, and $50^{\circ}C$ hot air thawing nearly negligible.

• Journal of Food Hygiene and Safety
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• v.3 no.1
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• pp.19-26
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• 1988

Most of meat spoilage bacteria area Gram negative, which are very sensitive to freezing ; for instance , 90% of E. coli cells are killed or sub-lethally injured by freezing at -3$0^{\circ}C$, and the freeze-injury rate is dependent upon freezing rate. Since the injured bacterial cells are sensitive to selective agents, they fail to multiply in selective media. Injured bacterial cells are, however, capable of spontaneous repair at appropriate environmental and nutritional conditions . Enumeration of injured bacterial cells involves artificial induction of repair at these conditions. Cubic beef samples(3$\times$3$\times$3cm) were frozen at -6$0^{\circ}C$, -4$0^{\circ}C$, or -18$^{\circ}C$. The samples frozen at each temperature were thawed at 4$^{\circ}C$, 2$0^{\circ}C$, or by microwave . After these respective freezing an thawing treatments, the percentage of sub-lethally injured total coliforms out of total surviving ones was measured and compared. The results were as follows: 1. The interaction between freezing and thawing on injury rate was not significant. 2. The injury rates(as means of all three thawing treatments post-freezing) by freezing at -6$0^{\circ}C$, -4$0^{\circ}C$, or -18$^{\circ}C$ were 32.2$^{\circ}C$ and 19.2$^{\circ}C$ respectively . 3. The injury rates(as means of all three freezing treatments)by thawing at 4$^{\circ}C$, 2$0^{\circ}C$, or by microwave were 49.3%, 11.7% and 21.0% respectively. The highest injury rate was caused by freezing at -6$0^{\circ}C$ and subsequent thawing at 4$^{\circ}C$. However since the injury rates by freezing treatment were not significantly different, freezing at -18$^{\circ}C$ and subsequent thawing at 4$^{\circ}C$ can also be recommended , from an economic perspective.