• Proceedings of the Korean Society of Postharvest Science and Technology of Agricultural Products Conference
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• 2007.11a
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• pp.169.1-169.1
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• 2007

• Korean Journal of Food Science and Technology
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• v.20 no.6
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• pp.820-826
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• 1988

The freezing point$(t_f)$, latent heat of freezing$({\triangle}\;H_f)$ and kinetic constant of fleering$(k_f)$ were determined from DSC thermogram at cooling rate $-2.5^{\circ}C/min{\sim}-10.0^{\circ}C/min$. The freezing point of various starches was decreased with an increase in cooling rate, and that of whole starches were lower than defatted starches. Changes of the latent heat of freezing was not observed at above cooling rate $-2.5^{\circ}C/min$. The latent heat of freezing$({\triangle}\;H_f)$ could be deduced as a function of water content(W) as follows: ${\triangle}\;H_f=0.700W-13.048$, (Kcal/kg) $(35%{\leqq}W{\leqq}70%)\;{\triangle}\;H_f=1.569W-73.861,\;(Kcal/kg)\;(W{\geqq}70%$) In the water content range $35{\sim}90$(wt %), the activation energy of various starches in freezing process was determined $126{\sim}270$ Kcal/mol.

• Food Science and Preservation
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• v.23 no.3
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• pp.438-444
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• 2016

This study was performed to determine the optimal freezing point for the reliable cold storage of Korean agricultural products, and to provide basic data for determining the storage temperature based on the quality characteristics. Additional supercooling temperature analysis was conducted to explore the possibility of supercooling storage. To determine the effects of quality characteristics on the freezing point, the hardness, acidity, moisture and sugar content were analyzed. The crops were frozen using customized cooling unit and their freezing and supercooling points were determined based on their heat release points. The freezing temperatures of garlic, leek, cucumber, hot pepper, grape, oriental melon, netted melon, peach, cherry tomato, plum, daikon, sweet persimmon, apple, sweet potato, mandarin, pear, and strawberry were -1.6, -0.5, -0.5, -0.7, -1.6, -1.6, -1.3, -0.8, -0.3, -1.1, -0.3, -1.7, -1.5, -1.5, -0.8, -1.5, and -$0.9^{\circ}C$, respectively; otherwise, supercooling points were -7.8, -3.7, -3.3, -4.9, -5.7, -4.6, -2.8, -3.3, -5.9, -4.2, -0.8, -4.7, -3.2, -3.7, -4.7, -4.2, and -$3.4^{\circ}C$, respectively. These results suggest that the ideal freezing temperature of crops could be estimated through freezing point depression because of their sugar content, and this technique should be used to maintain an optimum storage temperature. However, cold storage is complicated and further study is required because of the effects of long-term cold storage on the crops.

• Journal of the Korean Society of Food Culture
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• v.20 no.4
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• pp.391-396
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• 2005

This study investigated the optimal amount of FDKP(Freeze Dried Kimchi powder) to be added in BFS(breakfast sausage) in order to develop a new Korean style processed food, which can be used as a useful export item. The results of the study suggested that BFSs prepared with FDKP were more favored than BFS without FDKP. The specific findings are as follows: The BFS added with 3% FDKP was favored most in color, taste, softness and overall acceptability by the trained sensory panels. However, in case of unbaked BFS, 9% addition of FDKP was found to have preferred color. Overall, this study suggests that 3% of FDKP was optimal for the newly developed Kimchi BFS. On top of that this study also showed possibility of standardization of product using Korean traditional Kimchi.

• Korean Journal of Food Science and Technology
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• v.20 no.6
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• pp.827-833
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• 1988

The objectives of this investigation were to develop an improved analytical method and to review with respect to experimental parameters and thermo-physical properties influencing the freezing time prediction. The results indicate that the relationship between freezing time and product size is dependent on the surface heat transfer coefficient. As the magnitude of surface heat transfer coefficient decreases, the influence of product size on freezing time becomes more profound. But the freezing time does decrease slightly as the coefficients are increased to values greater than 150 $w/m^2^{\circ}C$. In addition, influence of thermo-physical properties on the freezing time prediction shown generally density, water content, specific heat and thermal conductivity, in order of % difference. Multiple linear regression equation for freezing time prediction were obtained with respect to 4 different food materials with varying thickness.

• Journal of the Korean Geotechnical Society
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• v.15 no.6
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• pp.297-306
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• 1999

In this research, the frost heave mechanism of the weathered tuff soil sampled from the area tying between Ulanbator and Beijing was studied. The frost heave tests were carried maintaining the constant temperature at both upper$(+5^{\circ}C)\; and\; lower(-5^{\circ}C)$ ends of the sample. Here, main emphasis is given on variation of the freezing point depression with the variation of applied overburden pressure. The expansion of ice lens and migration of the pore water towards freezing front were observed in the test. It was found that with the increase in overburden pressure there is decrease in heave rate and increase in the absolute value of a segregation-freezing temperature. Hence the equation between segregation-freezing temperature and overburden pressure could be suggested. Also the water content of the samples at the frozen side was shown to be higher than those at the unfrozen side. Similarly, the water at warmer part of the frozen tuff was found much higher than that of the cooler part.

• Food Engineering Progress
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• v.22 no.4
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• pp.321-327
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• 2018

The main purposes of this study were to identify the factors affecting the supercooling property and to improve the possibility of supercooling storage of fruits and vegetables. Freezing point and nucleation temperature, moisture content, hardness, sugar content, and pH of nineteen fruits and vegetables were measured and Pearson correlation analysis was performed. Freezing point showed a statistically significant correlation with moisture content and sugar content (p<0.01), while ice nucleation temperature showed a correlation (p<0.05) only for sugar content. In particular, the water content and sugar content did not show any correlation with the freezing supercooling difference (FSD). From the correlation analysis between FSD, aerobic bacteria, lactic acid bacteria, yeast, and mold, FSD showed a correlation (p<0.01) with aerobic bacteria. The experiments of the saline solutions inoculated with aerobic bacteria at different concentrations showed FSDs of about 2 for saline inoculated with 9.4 log CFU/mL and about 6 for saline inoculated lower than 5 log CFU/mL. Therefore, the aerobic bacteria concentration was determined to be a key factor affecting the supercooling storage of fruits and vegetables.

• Maxillofacial Plastic and Reconstructive Surgery
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• v.13 no.4
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• pp.355-369
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• 1991

미세수술을 이용한 재건외과 분야에서 빈번히 혈관이식이 요구된다. 이러한 경우 자가정맥이 가장 널리 사용되고 있으며 그의 신뢰성도 인정되어 있다. 그러나 정맥 채취에 따르는 부가적인 수술이 요구되며 혈관 공여부에 또다른 결손을 초래한다. 동결건조동종정맥은 이러한 점을 보완하고 자가정맥을 대체할 수 있는 잠재성이 있다. 이에 동결건조동종정맥의 효율성을 알아보고자 2.5cm 길이의 가토대퇴정맥을 $-65^{\circ}C$, 200 mtorr의 음압으로 동결건조시킨 다음 대퇴동맥 결손부에 동종이식하고(n=24), 신선한 가토대퇴정맥 동종이식군(n=24)과 자가정맥이식군(n=24)을 1주 간격으로 4주간 비교 관찰하였다. 2주 개존율은 동결건조동종정맥 이식군, 100%;동종정맥이식군, 50%; 자가정맥이식군, 100%이었으며 4주 개존율은 동결건조동종정맥이식군, 83.3%;동종정맥이식군, 50%;자가정맥이식군, 100%로서 동결건조처치만으로 동종정맥이식의 생존율을 증가시켰다. 미세임파구세포독성검사에서는 동결건조정맥의 항원성이 상당히 낮아져있음을 알 수 있었다. 그러나 동결건조정맥의 내막세포화가 주사전자현미경 및 광학현미경 소견상 자가정맥보다 지연됨이 관찰되었다. 이러한 결과를 종합해 볼 때 동결건조동종정맥은 아무런 처치를 하지않은 신선 동종정맥보다 현저한 장점이 있었지만, 자가정맥이식을 대신할 수 있는 보다 더 좋은 대체방법이라는 견지에서는 임상 적용이 어려울 것으로 사료되었다.

• Journal of the Korean Society of Food Science and Nutrition
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• v.12 no.2
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• pp.62-65
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• 1983

As a new practical method for preserving freshness of fish, partially frozen storage has been reported to be useful in terms of K-value, TBA value, sensory evaluation etc. In order to develop a storage procedure to be used in place of cooled or frozen storage for the preservation of precooked fish food, partial freezing for up to two to three weeks was examined using baked mackerel. The criteria for evaluation were made according to the changes in volatile basic nitrogen (VBN), thiobarbituric acid (TBA) value, viable bacterial number, pH, color difference and sensory evaluation in fish muscle. The changes in TBA value of baked muscle during storage at $-3^{\circ}C$ differed slightly from those obserbed during cooled ($5^{\circ}C$) and frozen storage ($-20^{\circ}C$). Partial frozen storage ($-3^{\circ}C$) was effective in prolong an induction period of lipid oxidation during early storage. VBN of baked muscle tends to increase slowly while pH value was decrease during storage and there was no observed significant differences among three different storage condition. Viable bacterial number of the baked mackerel muscle stored at $-3^{\circ}C$ showed significantly less than that stored at $5^{\circ}C$, and similar to that stored at $-20^{\circ}C$ (the levels of $10^2/g$). Judging from the results of sensory evaluation and experimental data, partial frozen storage at $-3^{\circ}C$ seems to be effective as means of short-period preserving baked mackerel.

• Culinary science and hospitality research
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• v.9 no.2
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• pp.115-126
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• 2003

Freeze-dried Kimchi powder has to be first produced to make Kimchi noodle. Two days, ten days, fifteen days and twenty-five days fermented Kimchi were analyzed respectively to obtain adequate material for freeze-dried Kimchi. Fourteen days' fermented Kimchi with pH 4.0∼4.7 and 0.5∼0.8% acidity was chosen for material for freeze-dried Kimchi, Fourteen days fermented Kimchi was first freeze-dried and powdered. Sensory evaluation was done to decide that 4% addition of the powdered material was optimal. The mixture of Kimchi noodle was analyzed into two perspectives; noodle and Kimchi. The analyzed factors of the mixture was a texture of noodle, color level, Kimchi flavor and its spiciness. The texture of noodle are nutty taste, softness, viscidity and oil flavor. Heavy oil flavor and nutty tasty decreased against the increase of Kimchi powder. Six percent addition of material showed a definite change to the mixture. More than six percent addition destroyed the texture of noodle into near crumbles. Four percent addition of material showed almost same as ordinary noodle texture. Therefore four percent addition of freeze-dried Kimchi was chosen optimal through sensory evaluation.