• Journal of the Korean Society of Food Science and Nutrition
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• v.27 no.3
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• pp.489-494
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• 1998

For the purpose of improving the qualities of popcorn, potato, frozen hotdog and steamed egg, the effects of food height(0mm: HO, 5mm: H5, 10mm, 15mm: H15) for microwave cooking on physicochemical properties were investigated. In popcorn, weight loss was decreased as height increased while volume of popcorn was increased, which indicated that popcorn was poped very well as height increased. H10 showed the highest taste score in sensory evaluation. In potato, degree of gelatinization was increased as hight increased. H10 showed the highest overall acceptance score. In frozen hotdog, hardness of hotdog was decreased as hight increased and H15 showed the lowest hardness score (408.8g). In steamed egg, H5 showed the highest temperature and H10 showed the highest overall acceptance score. Physicochemical properties of food were changed by heating height of microwave heating.

• Food Science and Preservation
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• v.4 no.2
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• pp.173-180
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• 1997

The effects of sugars and heating methods on the sugar infilteration, hardness, color and organoleptic characteristics were investigated for quality improvement of sugared chestnuts. Among the tested sugars, isomaltooligosugar was the most effective on the rate of sugar infilteration. High temperature increased the rate of sugar infilteration during sugaring process, but color and flavor were deteriorated at 9$0^{\circ}C$. The most suitable temperature for sugaring process was 7$0^{\circ}C$. The product sugared with fructooligosugar recoreded the highest score in hardness, odor and preference than any other sugars tested and increased the rate of sugar infilteration when mixed with sugar at same amount. The changes of soluble solids in chestnuts boiled with microwave oven were ranged from 18。Brix to 32。Brix, while chestnuts heated in general were from 18。Brix to 28。Brix. Chestnuts boiled with microwave heating were sugared rapidly. The hardness of boiled and sugared chestnuts was lower when treated with microwave than with general heating. Hunter's L and b value of sugared chestnut treated with microwave decreased during processing but a value somewhat increased.

• Journal of the Korean Society of Food Science and Nutrition
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• v.27 no.1
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• pp.109-114
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• 1998

For the purpose of improving quality of defrosted-frozen chicken leg, beef and yellow corvina, the effects of height(0mm : H0, 5mm : H5, 10mm : H10, 15mm ; H15) for microwave defrosting on their physicochemical properties were investigated. In frozen chicken leg, color values were not significant different between each treatment while H10 and H15 had the highest score on appearance. Hardness of defrosted chicken leg was increased as height increased. In frozen beef, temperature of beef after defrosting increased as hight increase and H10 had the highest appearance score. In frozen yellow corvina, H10 had the highest hardness and appearance scores. Physicochemical properties of color, texture and appearance of microwave-defrosted frozen food were changed by height within microwave oven.

• Korean Journal of Crystallography
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• v.9 no.1
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• pp.44-47
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• 1998

A reduction/oxidation reaction between A1 metal powder and SiO2 powder was performed by Self-propagating High-temperature Synthesis (SHS) reaction induced by microwave energy to produce a composite of Al2O3 and Si powders by using a 2.45 GHz kitchen model microwave oven. A Microwave Hybrid Heating(MHH) method was applied by using SiC powders as a suscepting material to raise the temperature of the disk samples and the heat increase rate of over 100℃/min were obtained before the reaction. The reaction started around 850℃ and the heat increase rate jumped to over 200℃/min after the reaction took place.

• Journal of the Korean Ceramic Society
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• v.35 no.11
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• pp.1197-1202
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• 1998

To check the possibility for microwave sintering of MLCC(multi layer ceramic capacitor) the tape cast-ed BaTiO3 thick films in zirconia insulation box were sintered by the domestic microwave oven. Microwave sintered samples had higher density lower porosity than coventionally sintered ones. but they didn't show Z5U electrical properties due to short sintering time about 15 minutes.

• Korean journal of food and cookery science
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• v.8 no.1
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• pp.15-20
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• 1992

The changes in color of spinach leaves upon blanching in boiling water and by microwave oven were investigated. The noticible changes in color of leaves were observed above $70^{\circ}C$. The values of L (lightness), a (redness) and b (yellowness) were decreased upon blanching. The value of the under surface of leaves was decreased by 2~3 times compared to that of the upper surface. The noticible color changes occured from 15 sec and the absorbance at 432 nm of water increased rapidly from 2 min of blanching in boiling water. Salt (0.5 and 0.9%) decreased the absorbance at 432 nm of water. The changes of L and b of the under surface of leaves upon heating with a microwave oven were less compared with those in boiling water. Based on the color differences of leaves upon blanching in boiling water, the optimum ratio of spinach to water was 1:4 or 1:5.

• Food Science and Preservation
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• v.4 no.1
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• pp.17-25
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• 1997

The effects of microwave treatment on the perservation of foods, such as a seaweed soup and sea stoned radish shreds, were studied. Microwave treatment of microbial cell suspensions revealed that viable cells decreased dramatically when heated to 6$0^{\circ}C$. However, it was unlikely that microwave treatment to 60 is enough to decrease the viable cell counts efficiently in a seaweed soup and radish shreds. It was thought that microwave heating to at least 7$0^{\circ}C$ as a final temperature was an important factor to reduce microbial cell counts in foods. When foods were heated to 7$0^{\circ}C$ with a repetitive 15 sec "on" followed by 30 sec "off", no big differences were observed in viable counts during storage at 2$0^{\circ}C$ for 3 days, as compared to those treated with a full power. The microwave treatment with three stages was designed to solve problems associated with variations depending on food volumes and difficulties of heat diffusion in a solid food to be irradiated with a microwave oven. The three stage method was found to have a similar efficiency in the reduction of viable cell counts in foods to microwave treatment at a full power and to conventional methods, such as water bath heating or boiling for 3 min with a gas range.in with a gas range.

• Proceedings of the KIPE Conference
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• 2002.11a
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• pp.108-111
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• 2002

For the global microwave market, high RF power or deluxe model is applying for Inverter gradually. In this study, 120V/1200W high power Inverter was proposed and verified by an optimized design of PFM-type. Especially the steady power output control was fulfilling at +/- $10\%$ input voltage variation.

• Korean Journal of Food Science and Technology
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• v.26 no.6
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• pp.696-703
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• 1994

The purpose of this study was to investigate the gelatinization properties of potato starch heated with microwave. Two types of potato starches were prepared; In group A raw potato starch was heated with microwave and in group B potato starch was isolated from potato heated with microwave. Both groups were exposed to the microwave energy in a 560W, 2,450 MHz oven for 60, 120, 180 and 300 seconds. Gelatinization behaviour by DSC made a few differences according to the ratio of starch to water. As the microwave heating time took longer, gelatinization temperature and gelatinization $enthalpy({\bigtriangleup}H_1)$ were decreased in and melting $enthalpy({\bigtriangleup}H_2)$ was increased in group A. Whereas they were increased in group B. In both groups, maximum viscosity in gelatinization by Brabender amylogram was decreased by microwave heating. Then the peak of the maximum viscosity was shifted to higher temperature and cold viscosity was slightly increased. In group A, viscosity in gelatinization and light transmittance by NaOH was increased in initial stage and gel volume in gelatinization by KSCN was decreased. On the other hand, in group B, viscosity by alkali was slightly decreased, but light transmittance by NaOH was almost never changed. Gel volume is decreased like group A.

• 한국신재생에너지학회:학술대회논문집
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• 2009.06a
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• pp.889-892
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• 2009

A microwave plasma torch at the atmospheric pressure by making use of magnetrons operated at the 2.45 GHz and used in a home microwave oven has been developed. This electrodeless torch can be used to various areas, including industrial, environmental and military applications. Although the microwave plasma torch has many applications, we in the present work focused on the microwave plasma torch operated in pure steam and several applications, which may be used in future and right now. For example, a high-temperature steam microwave plasma torch may have a potential application of the hydrocarbon fuel reforming at one atmospheric pressure. Moreover, the radicals including hydrogen, oxygen and hydroxide molecules are abundantly available in the steam torch, dramatically enhancing the reaction speed. Also, the microwave plasma torch can be used as a high-temperature, large-volume plasma burner by injecting hydrocarbon fuels in gas, liquid, and solid into the plasma flame. Lastly, we briefly report an underway research, which is remediation of soils contaminated with oils, volatile organic compounds, heavy metals, etc.