• 한국식품영양학회지
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• 제11권4호
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• pp.409-415
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• 1998

This study was carried out to investigate the effects of freezing temperature on quality of vacuum packaging freezed beef. In case of thaw drip loss, the freezing of -3$^{\circ}C$ and -20$^{\circ}C$ were 5.23% and 5.17% to 60 days respectively, were increased significantly during freezing. The cooking loss of water bath and pan were increased significantly during freezing than the beginning of freezing, but were no different between -3$^{\circ}C$ and -20$^{\circ}C$. The salt soluble protein extractability was decreased during freezing, the -20$^{\circ}C$ freezing was higher than -3$^{\circ}C$freezing. The water soluble protein extractability was increased during freezing higher than during freezing. The myoglobin denatured percentage of the -3$^{\circ}C$ freezing was higher than -20$^{\circ}C$ freezing, the 15 days storage of -3$^{\circ}C$ freezing was highest to 96%. The shear force value was not change during freezing, the myofibrillar fragmentation index during freezing was higher than the beginning of freezing, but was not change during freezing. The pH was decreased to freezing 45 days, after that increased.

• 한국식품영양학회지
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• 제11권5호
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• pp.482-487
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• 1998

This study was carried out to investigate the effects of freezing temperature on quality of thawed beef loin. In case of thaw drip loss, the freezing of -3$^{\circ}C$ and -2$0^{\circ}C$ were higest by 3.4% to 30 days and by 1.8% to 60 days, respectively. And the thaw drip loss of -3$^{\circ}C$ freezing was more than -2$0^{\circ}C$ freezing. The cooking loss of water bath and pan boiling were increased significantly during freezing than the beginning of freezing, but were not different -3$^{\circ}C$ and -2$0^{\circ}C$. The salt soluble protein extractability was decreased during freezing, the -2$0^{\circ}C$ freezing was higher than -3$^{\circ}C$ freezing. The water soluble protein extractability of -3$^{\circ}C$ freezing was not significant different during freezing storage, that freezed at -2$0^{\circ}C$ was increased during freezing. The "L" value of the beginning of freezing was higher than during freezing, the "a" value was not different during freezing, and the "b" value during freezing was higher than the beginning of freezing. The myoglobin denatured percentage of the -3$^{\circ}C$ and -2$0^{\circ}C$ freezing were highest by 94.4% to 45 days and by 94.0% to 15 days, respectively. The shear force value during freezing was higher than the beginning of freezing, the myofibrillar fragmentation index was not significant different during freezing. The pH was increased to freezing 30 days, after that was decreased.ays, after that was decreased.

• 한국축산식품학회지
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• 제41권6호
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• pp.1012-1021
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• 2021

This study evaluated the effect of freezing rate on the quality characteristics of pork loin to establish an objective standard for rapid freezing. To generate various freezing rates, three air flow rates (0, 1.5, and 3.0 m/s) were applied under three freezing temperatures (-20℃, -30℃, and -40℃). Based on the results, freezing rates ranged from 0.26-1.42 cm/h and were graded by three categories, i.e, slow (category I, >0.4 cm/h), intermediate (category II, 0.6-0.7 cm/h) and rapid freezing (category III, >0.96 cm/h). Both temperature and the air flow rate influenced the freezing rate, and the freezing rate affected the ice crystal size and shear force in pork loin. However, the air flow rate did not affect thawing loss, drip loss or the color of pork loins. In the comparison of freezing rates, pork belonging to category II did not show a clear difference in quality parameters from pork in category I. Furthermore, pork in category III showed fresh meat-like qualities, and the quality characteristics were clearly distinct from those of category I. Although the current standard for rapid freezing rate is 0.5 cm/h, this study suggested that 0.96 cm/h is the lowest freezing rate for achieving meat quality distinguishable from that achieved with conventional freezing, and further increasing the freezing rate did not provide advantages from an energy consumption perspective.

• 한국지반공학회:학술대회논문집
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• 한국지반공학회 1994년도 연약지반처리위원회 봄 학술발표회 논문집 연약지반처리
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• pp.13-46
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• 1994

Artificial ground freezing methods have been applied to geotechnical construction projects for stabilizing earth materials and controlling water seepage into the ground. However, this can result in frost heaving and causes the same engineering problems as encountered with the natural freezing of soil. In natural freezing, the ground freezes from the surface downward. When artificial ground freezing is applied at a deep location, however, freezing is limited locally. The soil condition differs between them as follows: Natural freezing - unsaturated and without overburden pressure. Artificial freezing -- saturated and under overburden pressure. The authors investigated the practical application of artificial ground freezing and examined the frost behaviour of a saturated soil under overburden pressure. This paper presents the results obtained from experiments concerning frost heaving and discusses frost heaving at the freezing site.

• 한국콘크리트학회:학술대회논문집
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• 한국콘크리트학회 2000년도 가을 학술발표회 논문집(II)
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• pp.1267-1272
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• 2000

When fresh concrete is exposed to low temperature, the concrete may suffer frost damage due to freezing at early ages and strength development may be delayed. These are problems on cold weather concrete. One of the solution methods for resolving these problems has been to reduce the freezing temperature of concrete by the use of chemical admixtures called Accelerators for freezing resistance. Therefore, in this study, we executed freezing temperature of mortar, setting and strength properties with using water reducing accelerator and accelerators for freezing resistance which are producted internationally. As a result of this experiment, the freezing temperature of mortar is lower and the setting property is promoted when the admixing content of accelerators for freezing resistance is increased. Moreover, the compressive strength of mortar used accelerators for freezing resistance represented the result which is similar with result of analysis of compressive strength increase with using logistic curve formula, but in the case of plain and using water reducing accelerator, there is no relation between logistic curve formula, maturity and compressive strength.

• 콘크리트학회논문집
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• 제11권4호
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• pp.117-127
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• 1999

In concrete incorporating high volume ground granulated blast-furnace slag that has frozen at early age, to evaluated the results of resistance to freezing and thawing is very difficult because the hydration of the concrete increases over the duration of rapid freezing and thawing test. Hence, the dynamic modulus of elasticity of specimens after freezing and thawing will be favorable results unless the hydration effect is taken into consideration. In this study, a method of evaluating to the resistance to freezing and thawing of concrete subjected freezing at early age, in which the effect of hydration is modified for its increase during rapid freezing and thawing test, is investigated.

• 한국식품영양과학회지
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• 제24권6호
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• pp.984-989
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• 1995

The concentration-efficiencyh of blue dextran solution in the progressive freeze-concentration was related to the freezing conditions such as the freezing speed and the stirring speed in the solution phase. From the theoreticla balance equation of heat and mass transfer at freezing front, the relationship between the freezing conditions and the ice structure at freezing front was drived. A high freeze-concentration efficiency was obtained under the operating conditions represented by a low speed of freezing and a high speed of stirring. The operating conditions were related to a smooth solid-liquid interface and these results were well explained by the theoretical equation. Effect of the solute component size on the concentration efficiency in the progressive freezeconcentration was also tested. The concentration efficiency of latex particles showed a lower value than that of blue dextran, however, its difference was insignificant.

• 한국임상수의학회지
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• 제8권2호
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• pp.183-190
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• 1991

Pellet and straw methods in canine semen freezing are compared with respect to motility, viability and acrosome demage of sperm during each of the two major processing steps, to prior-freezing and to frozen-thawing. Senen was extended with a tris-buffered egg yolk contained 4% glycero1 Pellet freezing in the hole of dry ice and straw freezing on the surface of liquid nitrogen were carried out, respectively. The frozen semen 10 days after storage in liquid nitrogen container. wao thawed. In the comparison of two freezing methods, the straw freezing method with 42.7% in motility. 49.2% in viability and 0.186 acrosome score after thawing seems to be superior to the pellet freezing method with 31.2%, 34.5% and 0.314%, respectively. Sperm motility of processing step to frozen-thawing against decrease rate 12.67% to Prior freezing appeared of 33.84% and 49.37% in straw and pellet freezing and increase of 0.02 in acrsomal score to prior freezing appeared of 0.08 and 0.21 in straw and pellet freezing method to frozen-thawing

• 한국응용과학기술학회지
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• 제37권6호
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• pp.1507-1516
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• 2020

본 연구는 도로 노면결빙 판정 알고리즘을 적용하여 도로결빙 구간에 대한 시나리오를 분석하였다. 도로결빙 알고리즘 적용을 위해서, 도로 결빙에 대한 영향인자를 검토하고, 분석을 위해서 목감IC, 정릉터널, 성산대교, 염창교 등 4지점의 관측자료를 활용하였다. 관측소는 모두 고속화도로에 설치되어 있으며, 도로 결빙 특성 분석을 위하여 분류하였다. 도로 결빙 판정 알고리즘의 노면온도-노점온도 차가 3℃ 이하일 때 도로결빙 발생 구간을 확인하고 결빙 구간의 노면상태와 수막두께 변화를 통해 도로 결빙 판정을 도출하였다.

• 한국수산과학회지
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• 제19권1호
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• pp.27-35
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• 1986

붕장어와 방어를 시료어로 하여 이것을 빙장, partial freezing 및 동결 저장을 하여 두고 저장 중의 시료어의 pH, VBN 및 K 치의 변화, 지질의 POV와 TBA 치의 변화 및 육단백질의 조성변화를 분석하여 partial freezing에 의한 선도유지효과를 검토하고, 붕장어에 대하여는 저장기간 별로 어묵을 제조하여 겔강도, 절곡강도, 압출수분율 및 texture 등을 측정하여 저장기간에 따른 시료어육의 어묵형성능의 유지효과도 검토하였다. 1. 저장 중의 시료어의 pH가 최저치에 달하는 기간은 동결 저장, partial freezing 및 빙장의 순으로 길었다. VBN의 변화는 붕장어를 빙장한 경우, 저장 9 일째 이후 급격한 증가를 나타내었으나, partial freezing과 동결 저장의 경우에는 저장기간에 따른 변화는 거의 없었다. 방어는 partial freezing 및 동결 저장의 경우에도 완만하게 증가하는 경향을 나타내었다. 2. 저장 중의 K치의 변화에 있어서, 9 일간 partial freezing한 경우, 붕장어는 $13\%$, 방어는 $26\%$를 나타내었으며, 동결 저장의 경우에는 두 시료어 모두가 큰 변화를 보이지 않았다. 그리고. 저장 중의 K치의 증가속도는 숭어보다 다소 완만한 경향을 나타내었다. 3. TBA치의 변화에 있어서, 붕장어 및 방어를 빙장한 경우에는 저장기간에 따라 점차 증가하는 경향을 나타내었으며, 동결 저장의 경우에는 거의 변화가 없었다. Partial freezing의 경우, 붕장어는 큰 변화가 없었지만, 방어는 초기에 약간 상승하는 경향을 나타내었다. 한편, POV의 변화에 있어서는, 붕장어와 방어의 증가폭이 빙장, partial freezing 및 동결 저장 순으로 켰으며, 방어가 붕장어에 비하여 증가속도가 다소 큰 경향을 나타내었다. 4. 저장 중의 단백질조성의 변화는 붕장어와 방어의 근원섬유단백질이 저장 9 일째에 생시료에 대하여 빙장의 경우는 각각 약$25%$, 약 $16\%$, partial freezing의 경우는 시료어 모두가 약 $10\%$ 감소하였으며, 동결 저장의 경우에는 저장 15 일째에 각각 약 $11\%$ 및 $4\%$ 감소하였다. 알칼리 가용단백질은 저장 9일째에 붕장어와 방어가 빙장의 경우, 각각 약 6.3배, 약 3.3배, partial freezing의 경우 약3.4배, 약 1,7배, 동결 저장의 경우에는 저장 15 일째에 각각 약 3.2배 및 약 1.5배의 증가를 나타내었으며, 전반적으로 붕장어가 방어에 비하여 변화폭이 켰는데 숭어에 비해서는 붕장어가 켰으며, 방어는 적었다. 5. 붕장어를 저장 조건 별로 제조한 어묵의 겔강도, 절곡강도 및 texture의 저장기간에 따른 감소율은. 빙장의 경우가 가장 컸고, partial freezing및 동결 저장의 경우가 다소 완만하게 감소하였다. 10 일간 저장한 시료어로 제조한 어묵의 겔강도는 빙장을 한 것이 대조구의 것의 약 $35\%$, partial freezing을 한 것이 약 $74\%$, 동결 저장한 것은 약 $76\%$를 나타내었다. 어묵의 압출수분율은 10일간 저장한 시료어의 경우, 빙장한 것이 약 1.6배, partial freezing을 한 것이 약 1.2배, 동결 저장을 한 것이, 약1.1배의 증가를 나타내었는데, 저장기간에 따른 물성의 변화는 숭어에 비하여 붕장어가 적었다.