• Journal of Advanced Marine Engineering and Technology
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• v.25 no.6
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• pp.1250-1259
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• 2001

This study was experimentally performed to investigate sea water freezing behavior along parallel cooled plate with bubbly flow The experiments were carried out for a variety of parameter, such as sea water velocity, air-bubble flow rate, and cooled-plate temperature. The shape of freezing layer, freezing rate and salinity of frozen layer were observed and measured. It was found that the experimental parameters gave a great influence on the freezing rate and the salinity of the frozen layer.

• Proceedings of the Korea Concrete Institute Conference
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• 2010.05a
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• pp.391-392
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• 2010

The frozen road is effected as major cause of car accident in winter. Especially, road surface freezing on the highway can lead to fatal accident. The accident by frozen road can effectively reduced by prevent road surface freezing before it frozen as evaluate road surface condition. Therefore, this study installed thermometer in each depth of concrete pavement for evaluate road surface conditions which freezing chronically. The result of this study will be used as preliminary data for predict before freezing.

• Journal of Korean society of Dental Hygiene
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• v.21 no.5
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• pp.517-526
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• 2021

Objectives: This study was conducted to analyze the sugar content, acidity, and viscosity of the Korean frozen desert. Methods: A total of 60 types of frozen desserts marketed in Korea were randomly selected and classified into frozen desserts, milk-fat ice cream group, and non-fat ice cream group according to the classification criteria for frozen desserts. Each product was treated under the same conditions to investigate the component of each product, and sugar content, acidity, and viscosity were measured. Frequency analysis and one-way ANOVA were performed. Results: As a result of analyzing the characteristics related to dental caries activity by group, the frozen dessert had the lowest average pH of 3.67, and the sugar content was significantly higher in the milk-fat group (33.22) and non-fat group (32.89) than in the frozen dessert. The viscosity was also the highest in the milk-fat group at 32.62, and the frozen dessert was significantly lower at 9.42. Conclusions: Due to the abnormal temperature and spread of the coronavirus, consumption of frozen desserts at home is on the rise. To prevent dental caries in children, education is needed for children and their guardians for proper oral care after eating frozen desserts.

• Clinical and Experimental Reproductive Medicine
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• v.18 no.1
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• pp.55-61
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• 1991

In order to increase the pregnancy rate by means of cryopreservation of the excess oocytes in IVF-ET program, the survival rate of the frozen-thawed oocytes of mouse was examined according to the stages of maturation, cryoprotectants and their treatment. The results were summarized as follows. First, during the continuous treatment with cryoprotectant media, the survival rate of oocytes was higher in DMSO than in PROH, and higher at low temperature($4^{\circ}C$) than at room temperature($25^{\circ}C$). Second, as regard with the maturation of immature(GV-intact) oocytes after treatment with cryoprotectant media, the rate of maturation in DMSO-treated group(52%) was higher than in PROH-treated group(35%). Third, according to the treatment of cryoprotectant media, the survival rate of frozen-thawed oocytes in DMSO-treated group (45%) was higher than in PROH-treated group(29%), and that of oocytes in DMSO 4-step treated group was higher than any other groups. Finally, in the post-thaw oocytes frozen at various stage of maturation, the survival rate of immature oocytes with GV was the highest in all groups. These results suggest that in the cryopreservation of mouse oocytes, DMSO was better than PROH as cryoprotectant, in treatment of cryprotectant the multi-step treatment was better than single-step, and the post-thaw survival rate of oocytes was closely related to the maturity of oocytes. It is assumed that the highest survival rate of mouse oocytes with GV is due to the stability of the structures in nucleus and intracelluar organelles, and of physiological function.

• Food Science and Preservation
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• v.14 no.5
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• pp.469-473
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• 2007

The optimal formula for non-frozen pound cake was sought using a central composite design with a quadratic model, by response surface methodology (RSM). Behavior on supercooling, freezing time, theological properties, and sensory attributes of pound cake were studied by using various concentrations of sugar, sorbitol, and glycerol. The freezing temperature of standard pound cake was $-16.16^{\circ}C$. The hardness, freezing point temperature, and sensory properties were shown as a quadratic relationship whereas moisture content was analyzed by a linear model. Optimized formula for non-frozen cake were suggested to include (sugar:sorbitol:glycerol) 77.6:0.0:20.4, 60.0:32.8:16.4, and 70.8:11.2:19.6 (all % of total sugar) by RSM. The freezing tines of optimized non-frozen pound cake were reduced by $27{\sim}45%$. The freezing Points of optimized pound cake were depressed below $-20^{\circ}C$. Sorbitol and glycerol may be used as cryoprotectants and preserve the desired sensory attributes of pound cake at low temperatures.

• Magazine of the Korea Concrete Institute
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• v.10 no.4
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• pp.205-212
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• 1998

Frost damage of a storage tank for chemical admixtures caused by a low temperature in winter and quality deterioration of chemical admixtures have been often reported. However, there have been few regulations and researches related to the frost damage of chemical admixtures and facilities. Therefore, this paper is intend to investigate not only, the freezing points of chemical admixtures such as AE admixtures and water-reducing AE admixtures, etc., but also the quality variation of concrete used with chemical admixtures before freezing and after freeze-thaw cycles. According to the results of experiments, most chemical admixtures except anti-freezing agent and accelerating water-reducing AE admixtures should be kept from being frozen in low winter temperatures. However, full agitation of frozen chemical admixtures dose not cause the problems of concrete related to the quality of chemical admixtures.

• Journal of Navigation and Port Research
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• v.37 no.2
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• pp.129-135
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• 2013

Recently, waste water treatment system is developed in small and middle size to get more economic advantage. Freeze concentration system has high thermodynamic efficiency and low energy consumption, can re-use purified water and cold energy obtained from ice. This study was experimentally performed to investigate pollution containment in frozen layer by cooling wall temperature, air-bubble flow methods, initial ice-lining thickness of frozen layer in NaCl aqueous solution and the representative heavy metals, Pb and Cr aqueous solution. As the result, a decrease in the cooling wall temperature bring a higher growth rate of ice front and the more solute was involved in frozen layer. The method to inject directly air-bubble into ice-liquid interface through ring shape nozzle gave high purity of ice compared to indirect method. Ice lining in 5mm thickness resulted in frozen layer with higher purity than 1mm thickness.

• Food Science of Animal Resources
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• v.34 no.5
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• pp.597-603
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• 2014

In this study, the physicochemical and sensory quality characteristics due to the influence of various thawing methods on electro-magnetic and air blast frozen pork were examined. The packaged pork samples, which were frozen by air blast freezing at $-45^{\circ}C$ or electro-magnetic freezing at $-55^{\circ}C$, were thawed using 4 different methods: refrigeration ($4{\pm}1^{\circ}C$), room temperature (RT, $25^{\circ}C$), cold water ($15^{\circ}C$), and microwave (2450 MHz). Analyses were carried out to determine the drip and cooking loss, water holding capacity (WHC), moisture content and sensory evaluation. Frozen pork thawed in a microwave indicated relatively less thawing loss (0.63-1.24%) than the other thawing methods (0.68-1.38%). The cooking loss after electro-magnetic freezing indicated 37.4% by microwave thawing, compared with 32.9% by refrigeration, 36.5% by RT, and 37.2% by cold water in ham. The thawing of samples frozen by electro-magnetic freezing showed no significant differences between the methods used, while the moisture content was higher in belly thawed by microwave (62.0%) after electro-magnetic freezing than refrigeration (54.8%), RT (61.3%), and cold water (61.1%). The highest overall acceptability was shown for microwave thawing after electro-magnetic freezing but there were no significant differences compared to that of the other samples.

• The Korean Journal of Food And Nutrition
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• v.9 no.4
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• pp.424-429
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• 1996

In an attempt to evaluate the effect of six starch sources-potato starch acetate, corn starch acetate, waxy corn starch, corn starch, potato starch, and wheat starch on properties of frozen noodle, amylograph characteristics of starch-wheat flour composites, cooking quality, maximum cutting force and sensory properties of cooked frozen noodles were examined. Compared with 100% wheat flour as control, potato starch acetate and potato starch-wheat flour composites had slightly lower initial pasting temperature and wheat flour composites with acetylated starches, waxy corn starch and potato starch had slightly higher maximum peak viscosity. At cooking quality examination of noodles made from wheat flour-starch composites, volume and weight of cooked noodles were increased and cook loss was decreased with the addition of acetylated starches and waxy corn starch. Maximum cutting forces of cooked frozen noodles containing more than 15% of potato starch acetate and only 15% of corn starch acetate were higher than that of control. Other starches except potato starch improved sensory properties of cooked frozen noodles and the greatest positive effect was acetated potato starch.

• Korean Journal of Food Science and Technology
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• v.32 no.2
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• pp.335-340
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• 2000

The objectives of this research were to investigate changes in characteristics of whole frozen soft persimmon during storage, and to evaluate effects of blanching and addition of ascorbic acid on the quality of frozen soft persimmon puree. Reducing sugar, soluble solids and carotenoids contents in frozen soft persimmon did not change significantly during storage, while ascorbic acid of whole frozen soft persimmon and puree was continuously decreased during 8 months of storage. Whole frozen soft persimmon thawed at low temperature or by microwave oven did not show remarkable quality differences, whereas thawing puree resulted in a drastic decrease in consistency. Addition of ascorbic acid to puree reduced browning discoloration, but blanching puree caused significant loss of color and increase of consistency.