• 한국축산식품학회지
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• 제18권2호
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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.

• 대한가정학회지
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• 제35권2호
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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.

• 한국건축시공학회:학술대회논문집
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• 한국건축시공학회 2014년도 춘계 학술논문 발표대회
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• pp.284-285
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• 2014

In this study, effects of pore structure of ground granulated blast-furnace slag concrete on freezing-thawing resistance are reviewed. As a result, degradation of freezing-thawing resistance performance was occurred as replacement ratio of ground granulated blast-furnace slag increases under same specified concrete strength condition. It is considered that pore structure of internal binder affects freezing-thawing resistance performance.

• 한국건축시공학회:학술대회논문집
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• 한국건축시공학회 2014년도 추계 학술논문 발표대회
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• pp.190-191
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• 2014

The building insulation materials shall keep their thermal conductivity constant even when the freezing and thawing repeats for over a long time. But, in this condition of repeated freezing and thawing, the organic building insulation material may suffer the degradation in the thermal performance as the gas put into the insulation materials gets out slowly over a long time. Accordingly, in this study, the change in the thermal performance has been tested and evaluated when the repeated freezing and thawing cycles happen.

• 한국식품과학회지
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• 제22권2호
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• pp.123-128
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• 1990

여러 가지 해동방법 중에서 비교적 급속해동을 할 수 있는 열풍해동방법과 microwave 해동방법으로 냉동 돈육을 해동하여 해동육의 이화학적 성질을 조사하였으며, $4^{\circ}C$ 냉장해동육의 이화학적 성질을 비교하여 최적 해동방법을 모색하고자 하였다. 열풍온도를 높이고 해동육 표면온도를 낮출수록 열풍해동속도는 빨랐으며, microwave 해동시에는 출력이 크고 해동육심부온도가 낮을수록 해동속도가 빨랐다. 이 때 microwave 해동방법은 열풍해동방법보다 유의적으로 빠른 해동속도를 보였다. $4^{\circ}C$ 냉장해동육의 TBA가와 microwave 해동육의 TBA가는 유사하였으나 열풍해동육인 경우에는 열풍온도가 높아질수록 TBA가는 유의적으로 높았다. Microwave해동육의 가용성단백질추출성은 $4^{\circ}C$ 냉장해동육과 유사하였지만 열풍해동육보다는 높았다. 해동육의 보수성과 조리손실과의 관계는 고도의 상관성을 나타냈으며, microwave 해동육이 열풍 해동육보다 보수성이 좋았고 조리손실은 줄었다. 육표면에 존재하는 세균수는 $4^{\circ}C$ 냉장해동육에서보다 열풍 해동육과 microwave 해동육에서 적었다. 이상의 결과에서, 냉동육을 해동할 때, 육량감소를 줄이고 해동육의 기능성을 좋게 유지할 수 있는 해동조건으로서는 열풍해동에서는 $50^{\circ}C$ 열풍으로 육표면온도를 $25^{\circ}C$까지 해동시킬 때가, microwave로 해동하면 195W의 출력으로 육심부온도를 $-2^{\circ}C$까지 해동시키는 것이 가장 좋은 것으로 나타났다.

• 한국건축시공학회:학술대회논문집
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• 한국건축시공학회 2015년도 추계 학술논문 발표대회
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• pp.151-152
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• 2015

Concrete parking slab is often deteriorated severely after winter season because of concrete's freezing and thawing phenomenon. In this study, some methods to improve resistance against freezing-thawing is experimentally tested.: 1) concrete strength, 2) air content in concrete, 3) saw-cut effect and finish material. After experiment, in case of no finishes, 24MPa concrete with 4% air content is tested best result in terms of relative elastics modulus among testes ones. In case of concrete with finishes, all specimens are improved regardless of finishes compared to concrete with no finishes. Improvement degree compared to no finish is as follows : Polyurea > Resin-mortar > hardener and the number of improvement degree is 5, 4, 2% respectively. Further work is required considering construction site condition such as gaining water on surface and remicon in order to reflect site condition.

• 한국해양공학회지
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• 제23권5호
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• pp.54-60
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• 2009

Exposed to various environments, concrete confronts degradation by a lot of physical and chemical reaction. Though so many experiments and theorizations on the single condition of concrete degradation have been carried out by constant studies, the truth for now is that there are few studies on the compound phenomenon of degradation related with marine environments. Accordingly, this study measured the degree of degradation in the change of external shape, the change of unit weight and compressive strength, ultrasonic velocity test, and the change of length, etc. after exposing the specimen of cement mortar to the environment between 0 cycle and the maximum of 300 cycles under the condition of aquatic curing, freezing and thawing, and compound degradation, using mineral admixture effective for concrete degradation as a binder. The result indicated that the case of adding mineral admixture showed greater resistance than that of using OPC only, and specifically, the specimen with the additive of slag powder and three component system showed very excellent resistance to freezing and thawing, and compound degradation.

• 한국축산식품학회:학술대회논문집
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• 한국축산식품학회 2004년도 제34차 추계 국제 학술대회
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• pp.407-411
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• 2004

Ohmic heating occurs when an electric current is passes through food, resulting in a temperature rise in the product due to the conversion of the electric energy into heat. The time spent in the thawing is critical for product sterility and quality. The objective of this study is to conduct numerical modelling between the effect of ohmic thawing intensity on PTT(phase transition time) at constant concentration and the effect of matrix concentrations on PTT at constant voltage condition. the stronger ohmic thawing intensity resulted in decreasing the PTT. High ohmic intensity causes short PTT. And the higher gelatin concentration, the faster increment of PTT. A numerical modeling was executed to predict the PTT influenced by the power intensity using exponential regression and the PTT influenced by gelatin concentration using logarithmic regression. Therefore, from this numerical model of gelatin matrix, it is possible to estimate exact values extensively.

• 한국콘크리트학회:학술대회논문집
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• 한국콘크리트학회 1997년도 봄 학술발표회 논문집
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• pp.155-161
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• 1997

This Expriment is performed to describe the properties of the freezing-thawing and to find the method to enhance the freezing-thawing resistance of the high strength light weight aggregates concrete. For this purpose, we made 8 kinds of specimen of concrete mold. The light weight coarse aggregate concrete which contained AE was appeared in good condition and its durability index was more than 90% by the buffer action which owing to entained air. The light weight aggregates concrete which admixture of silca fume, was appeared that the durability index was 46.74% in spite of its high strength. I might conclude that the most important factor for freezing-thawing resistance of high strength light weight aggregate concrete is the entrained air.

• 한국조리학회지
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• 제7권1호
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• pp.91-105
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• 2001

Chou-cream bread and Red bean paste bread were made by sponge & dough method with the sweet dough formula. The bread quality was studied by the measurements of the temperature variation, the fermentation level of frozen dough in the special condition(dough conditioner of 5$^{\circ}C$, 10$^{\circ}C$, 15$^{\circ}C$, 20$^{\circ}C$ and 30$^{\circ}C$), the product volume and thesensory evaluation with frozen dough thawed, fermented and baked. When thawing temperature was low, the core temperature of frozen dough increased slowly and the time for thawing and fermentationwas long. In thawing and fermentation, the core temperature of Red bean paste dough increased faster than that of Chou-cream dough. When the thawing conditions of dough conditioner(retarder) were 20$^{\circ}C$ and 30$^{\circ}C$, the level of total time decrease for thawing and fermentation was 55 and 86 min in Chou-cream dough and 62 and 90 min in Red bean paste dough respectively in comparison to dough conditioner of 5$^{\circ}C$. In volume of baked products, they showed no significant difference for three weeks of storage, but slight difference for four weeks of storage. The result was that Chou-cream bread was larger than Red bean paste bread in the decrease of volume. In sensory evaluation, the bread quality became low according to the time. When stored for four weeks in the freezer, significant differences were found in Chou-cream vread, but slight difference appeared in Red bean paste bread. The research identified that Red bean paste dough was more effective in manufacturing time than that of Chou-cream dough, when thawing temperature was high, and if frozen dough was thawed in the retarder of lower than 20$^{\circ}C$, the bread quality in terms of volume and sensory evaluation had no significant difference in comparison to the none-freezing Red bean paste bread.