• Food Science and Preservation
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• v.17 no.6
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• pp.897-902
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• 2010

This study was conducted to investigate the effects of different cooking methods on the carotenoid content in genetically modified(GM) provitamin A-biofortified rice. The proximate components (moisture, protein, lipid, and ash) of GM rice were similar to those of conventional non-GM rice. Provitamin A-biofortified rice was cooked in various ways, including boiling in water and steaming/roasting. Carotenoid composition was determined by HPLC. Total carotenoid contents of provitamin A-biofortified brown and milled rice were $122.79{\mu}g/100g$ and $125.44{\mu}g/100g$, respectively. Compared with raw unprocessed samples, boiling caused approximately 20% carotenoid loss. In contrast, seaming/roasting decreased carotenoid content by 78%.

• Korean Journal of Food Science and Technology
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• v.34 no.6
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• pp.1123-1126
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• 2002

Kimchi was ripened at $25^{\circ}C$ for 4 days and heated at $100^{\circ}C$ for 10 or 40 min. pH of the ripened kimchi was not changed by heating, whereas sensory properties of kimchi, including overall acceptability, acidity, taste, odor, and texture, were improved, particularly by $100^{\circ}C/40$ min-heating. Allyl mercaptan, methyl allyl sulfide, dimethyl disulfide, diallyl sulfide, diallyl disulfide, and ethanol were detected in the ripened kimchi. Volatile odor components except ethanol and methyl allyl sulfide were removed by heating at $100^{\circ}C/10$ min, and the ethanol content was further reduced by heating at $100^{\circ}C/40$ min.

• Journal of the Korean Society of Propulsion Engineers
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• v.20 no.2
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• pp.46-55
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• 2016

The kinetic analysis of a heavily aluminized cyclotrimethylene-trinitramine(RDX) is conducted using differential scanning calorimetry(DSC), and the Friedman isoconversional method is applied to the DSC experimental data. The pre-exponential factor and activation energy are extracted as a function of the product mass fraction. The extracted kinetic scheme does not assume multiple chemical steps to describe the complex response of energetic materials; instead, a set of multiple Arrhenius factors is constructed based on the local progress of the exothermic reaction. The resulting reaction kinetic scheme is applied to two thermal decomposition tests for validating the reactive flow response of a heavily aluminized RDX. The results support applicability of the present model to practical thermal explosion systems.

• Journal of the Korean Society of Food Science and Nutrition
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• v.42 no.7
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• pp.1103-1108
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• 2013

This study was conducted in order to determine the effect of autoclave and microwave treatments on cookies. Wheat dough was treated in an autoclave (30 min), a microwave (1 min), and both autoclave and microwave (30 min/1 min). The treated dough was baked or non-baked and cookies quality was assessed. The pH, moisture content, color, and texture were measured, and sensory evaluation was performed. The pH showed a slight increase when dough was treated in a microwave (before baking) and decreased in both the autoclave and autoclave/microwave (after baking) treatments. The moisture content showed a significant increase, compared to the control, in autoclave treatments. Regarding surface color of cookies, lightness was decreased in all treatments and redness was higher compared with the control, except for microwave (before baking), and yellowness was lower compared to the control, except for microwave treatment (after baking). Hardness, gumminess, chewiness, and shear force showed a significant increase when dough was treated in an autoclave/microwave (after baking) compared to the control. In the sensory evaluation, color, taste, texture, shape, and overall preference of cookies treated with an autoclave/microwave (after baking) showed a low score. These results suggest that autoclaving and microwaving may reduce the quality of bread and that preparation of countermeasures is necessary.

• Proceedings of the Korean Society for Food Science of Animal Resources Conference
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• 2004.10a
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• pp.274-277
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• 2004

저장기간 중 닭고기 부분육의 가열감량은 저장 1일과 저장 9일에서 포장형태에 따라 차이는 없었으나, 전단력은 저장 6일에 랩트레이 포장과 진공포장 간에 통계적인 유의차이(p<0.05)가 있었으며, 보수력은 저장 9일에 렙트레이 포장과 진공포장 닭고기에서 통계적인 유의차이(p<0.05)가 있었다. 총균은 저장 9일에 랩트레이 포장이 5.26으로 가장 많이 검출되었으며, Coliform은 벌크포장과 랩트레이 포장은 저장 1일과 3일, 6일에는 검출되지 않았다. 지방산패도(TBARS) 값은 저장 3일에는 각 포장형태에 따라 벌크포장이 0.10mgMA/kg, 랩트레이 0.08mgMA/kg, 비닐포장 0.07mgMA/kg으로 통계적인 유의차(p<0.05)가 있었으나, 단백질변성(VBN) 값은 차이가 거의 없었다.

• Proceedings of the KIEE Conference
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• 2000.07c
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• pp.2174-2176
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• 2000

FDTD(Finite Difference Time Domain) 방법을 적용하여 마이크로웨이브 오븐 내부의 전자기장을 해석하였고, 적외선사진을 통하여 실험과 비교 검증하였다. 부하의 종류와 형태에 따른 전자기장의 패턴 변화를 고찰하였고, 여러 가지 포밍형태와 오프닝 형태에 따른 전자기장의 패턴을 적외선 사진과 비교하였다. 표면 보정 기법을 적용하여 부하표면에서의 전자파 패턴을 보다 정확히 예측할 수 있었으며, 또한 마그네트론의 공진 주파수에 따른 전자파 파워 패턴의 변화를 살펴 보았다. 이와 같이 개발된 마이크로 웨이브 오븐 내부의 전자파 해석 프로그램을 이용하면, 균일 가열 성능 향상을 위한 마이크로웨이브 오븐의 캐비티 설계 기간을 크게 단축할 수 있을 것으로 생각된다.

• The Korean Journal of Food And Nutrition
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• v.29 no.5
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• pp.670-676
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• 2016

In this study, we analyzed the utensils, covers and mats that were used for making meju, the shape of meju, and the heating method used for making meju from the 225 ways of preparing jang mentioned in the 32 volumes of the ancient cook books from 530 AD to 1950. The heating method of traditional meju bean and starch included 57 kinds of steaming, 59 of boiling, 21 of roasting + boiling, and 2 of cooking. The shape of meju included 41 kinds of egg, 27 of ball, 22 of lump, a kind of doughnut, 8 kinds of hilt, 6 of flat, 4 of chip, and a kind of square. Among the 72 gochoojang meju, the heating method of bean included 9 kinds of boiling, and 6 kinds of steaming; whereas the heating method of starch included 19 kinds of steaming of dough, 11 of rice cooking, and 5 of boiling of dough. The utensils for molding of bean meju were 49 kinds of straw sack, 14 of round straw container, 11 of heating bed, 7 of large straw bowl or Japanese-snailseed, 5 of jar, 4 of ditch, 3 of straw bowls, 2 of pottery steamer of dough, 2 of gourd, and a kind of long round bamboo bowl and sack of straw. The cover and the mat used for molding of meju included 36 kinds of straw, 17 kinds of paper mulberry leaf, 15 of wide straw seat, 14 of mugwort, 11 of pine tree leaf, 10 of soybean leaf, 6 of cocklebur leaf, 6 of sumac leaf, 6 of barley straw, 6 of mulberry leaf, 5 of fallen leaf, 5 of cogon grass, 4 of reed seat, 3 of scrap of cloth, 2 of Indian bean tree leaf, a kind of reed. There were only 5 kinds of hanging.

• Korean journal of food and cookery science
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• v.13 no.4
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• pp.434-439
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• 1997

The changes in thiamin content of an experimental product, 'Nuhbiani' were measured at the end of the process of simulated home prepared precook/storage/reheat system. The retention of thiamin in Nuhbiani after reheating by pan or microwave were compared. Statistical analyses indicated that there were no significant differences in thiamin contents due to the method of precooking and reheating. However, there were significant thiamin losses due to the storage period but no differences between the storage conditions. There were significant thiamin losses after 7 days of refrigeration (p < .05). The points causing significant thiamin losses in food product flow were precooking and 7 days of refrigerated storage.

• Korean Journal of Food Science and Technology
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• v.43 no.6
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• pp.683-688
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• 2011

This study was conducted to investigate the effects of different cooking methods on the nutrient composition of genetically modified (GM) provitamin A(PA)-biofortified rice. PA-biofortified rice was subjected to different cooking methods, namely boiling and a soaking, steaming and roasting process. The proximate components (starch, protein, lipid and ash) of raw PA-biofortified rice were similar to those found in the parental non-GM rice, and were not significantly affected by a conventional boiling treatment. When compared with raw rice, boiled PA-biofortified rice showed a similar nutrient composition, despite a slight reduction in a majority of its amino acid contents. However, the PA-biofortified rice that underwent the soaking/steaming/roasting process exhibited a significant reduction in a majority of its amino acids and mineral contents. This procedure also led to a significant reduction in carotenoid contents. The overall results of this study demonstrate that using a conventional boiling method for PA-biofortified rice retains nutrients better than a soaking/steaming/roasting method.

• Nuclear Engineering and Technology
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• v.27 no.3
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• pp.301-316
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• 1995

experimental and computational studies ore carried out to investigate the natural convection of the single phase flow in a tank with a heated horizontal plate facing downward. This is a simplified model for investigations of the influence of a core melt at the bottom of a reactor vessel on the thermal hydraulic behavior in a oater filled cavity surrounding the vessel. In this case the vessel is simulated by a hexahedron insulated box with a heated plate Horizontally mounted at the bottom of the box. The box with the heated plate is installed in a water filled hexahedron tank. Coolers are immersed in the U-type water volume between the box and the tank. Although the multicomponent flows exist more probably below the heated plate in reality, present study concentrates on the single phase flow in a first step prior to investigating the complicated multicomponent thermal hydraulic phenomena. In the present study, in order to get a better understanding for the natural convection characteristics below the heated plate, the velocity and temperature are measured by LDA(Laser Doppler Anemometry) and thermocouples, respectively. And How fields are visualized by taking pictures of the How region with suspended particles. The results show the occurrence of a very effective circulation of the fluid in the whole How area as the heater and coolers are put into operation. In the remote region below the heated plate the new is nearly stagnant, and a remarkable temperature stratification can be observed with very thin thermal boundary. Analytical predictions using the FLUTAN code show a reasonable matching of the measured velocity fields.