• 농업과학연구
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• 제20권2호
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• pp.181-188
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• 1993

한국산 가금육(육계, 재래닭, 오골계 및 꿩의 다리살과 가슴살)을 냉동후 $5^{\circ}C$, $20^{\circ}C$ 및 microwave로 해동하고, 해동방법에 따른 품질변화를 검토하여 다음과 같은 결과를 얻었다. 1. 해동 후 pH는 각 해동조건에서 냉동 전보다 모두 낮아졌으며 microwave 해동시의 pH 변화가 제일 적었고, 가슴살이 다리살 보다 큰 pH의 변화를 보였다. 또한 가금육의 품종별 비교에 있어서 pH의 저하는 오골계의 경우 가장 컸으며, 꿩에서 가장 적었다. 2. 해동후의 육즙 발생율은 microwave 해동시 가장 적었으며 부위별로는 다리살이 9~11%, 가슴살이 11~14%로 다리살의 경우 다소 낮아 보수력은 좋게 나타났다. 또한 품종별로는 육계 및 꿩에서의 육즙 발생율이 적었고 오골계에서 가장 많았다. 3. pH와 보수력은 1차함수의 관계로 pH가 낮아짐에 따라 육즙발생이 많이 생겨 보수력이 떨어지는 경향을 보였다. 이때 r값은 -0.82~-0.91의 값을 나타내었다. 4. 모든 가금육에 있어서 가슴살보다 다리살의 전단력이 컸으며, microwave 해동과 $5^{\circ}C$ 해동에 있어서는 비슷한 경향을 보였으며, $20^{\circ}C$ 해동에 있어서는 전단력의 큰 변화를 보여주었다. 5. 전단력과 pH는 1차 함수의 관계로 pH가 내려감에 따라 전단력이 저하하는 경향을 보였으며 이때 r값은 0.80~0.96의 값을 나타내었다.

• Journal of Biosystems Engineering
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• 제34권5호
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• pp.371-376
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• 2009

Microwave digestion is a preferred pretreatment method for agricultural samples because of its quick chemical reaction and minimum loss of analytes. In this research, a feedback temperature controller was developed to control the temperature inside a vessel for the microwave-assisted digestion system. An existing industrial microwave oven was fitted with the temperature controller for controlling inside temperature of the vessel. Four control methods, On/Off, proportional (P), proportional integral (PI), and proportional integral derivative (PID) were used and compared. Experimental results showed that PID control produced best temperature control performance. The PID controller could maintain the temperature of water sample and rice sample in the digestion system with error range of $-2.5{\sim}3.3^{\circ}C$ and $-1.9{\sim}0.5^{\circ}C$ at set temperature of $170^{\circ}C$, respectively.

• 한국안전학회지
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• 제27권1호
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• pp.63-69
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• 2012

Ready-mixed concrete(RMC) has been a major construction materials for infrastructures. However, RMC with poor quality is reported to be social issue since it directly user's safety and convenience. Because the properties of concrete as a construction material are greatly influenced by the variation of water content, to control water accurately is the most efficient method for the quality control in RMC industry. In this study, the automatic measurement technology of fine aggregate was developed by using the microwave moisture measurement. For the various conditions of fine aggregate such as moisture, temperature and pressure, the calibration curve of moisture measurement was obtained by using oven-dry method. From the infield and outfield test, it can be obtained that the accuracy of microwave moisture measurement is very high and the automatic system of microwave moisture measurement is very convenient and useful for quality control in RMC Industry.

• Bulletin of the Korean Chemical Society
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• 제35권3호
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• pp.905-907
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• 2014

The plasma and microwave surface treatments of carbon nanotubes that loaded on plastic substrates were carried out with expecting a change of carbon nanotube dispersion by increasing treatment time. The microwave treatment process was undergone by commercial microwave oven (800 W). The electrical property was measured by hall measurement and resistance was increased by increasing $O_2$ flow rate of plasma, suggesting an improvement of carbon nanotube dispersion and a possibility of controlling the resistances of carbon nanotubes by plasma surface treatment. The resistance was increased in both polyethylene terephthalate and polyimide substrates by increasing $O_2$ flow rate. Resistance changes only slightly with different $O_2$ flow treatment in measure rho for all polyimide samples. Sheet resistance is lowest in polyimide substrate not due to high carbon nanotube loading but due to tendency to remain in elongated structure. $O_2$ or $N_2$ plasma treatments on both polyethylene terephthalate and polyimide substrates lead to increase in sheet resistance.

• 한국축산식품학회지
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• 제36권4호
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• pp.538-546
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• 2016

This study was carried out to evaluate the effects of fat level on the microwave cooking properties of ground pork patties with NaCl (1.5%). Ground pork patties were processed from pork hams to achieve fat levels of 10%, 15%, 20%, and 25%, respectively. Each patty was cooked from a thawed state to 75℃ in a microwave oven at full power (700 W). After microwave cooking, protein content, moisture content, fat retention, and shear force values in patties decreased as fat level increased from 10 to 25%. As fat level increased, cooking time decreased but total cooking loss and drip loss were increased, whereas slight differences in diameter reduction and thickness of patties were observed. In raw patties, 10% fat patties had lower L* values and higher a* values compared to patties with more fat, but these differences were reduced when patties were cooked. Patties with 10% fat showed a more pink color on the surface and interior than patties with a higher fat content but more air pockets were noted in higher-fat patties. Higher-fat patties were more tender, juicy, and oily than lower-fat patties.

• Advances in materials Research
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• 제2권3호
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• pp.133-140
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• 2013

This paper aims to focus on the microwave processing of thick films which is a fast, cheap technique and could be the alternative to the currently used conventional high temperature processing technique. Microwave processing has gained worldwide acceptance as a novel method for heating and sintering a variety of materials, as it offers specific advantages in terms of speed, energy efficiency, process simplicity, finer microstructures and lower environmental hazards. Silver conducting thick films were prepared and processed in the household microwave oven. The films sintered at different time period by keeping the other parameter such as microwave power, film thickness etc constant. The microstructure analysis revealed that the surface morphology of the microwave processed films become compact with respect to the processing time. The sheet resistance for microwave sintered silver films is in the range of 0.003 to $1.207{\Omega}/{\Box}$ where as the films fired at 750 and $850^{\circ}C$ showed the resistance of 0.009 and $0.003{\Omega}/{\Box}$ which can be comparable. The results revealed that the microstructure of the microwave sintered films has more uniform and compact surface than that of the conventionally fired films. The paper reports upon the preparation of silver thick film by screen printing technique and processing the same by microwave which also compared with the conventionally processed thick films.

• 한국식품과학회지
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• 제32권3호
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• pp.654-658
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• 2000

Coca bean을 마이크로파로 roasting하고 그 향기성분의 변화를 methyl pyrazine류를 중심으로 살펴보고 이를 상법으로 roasting한 경우와 비교해 보았다. 전자렌지를 개조하여 마이크로파 roasting system을 설계하여 실험에 사용하였고 열전쌍을 이용한 온도측정법으로 cocoa bean의 품온을 측정하였다. 마이크로파 roasting은 roasting 시간을 30분으로 고정하고 온도를 110, 120, 130, 140 및 $150^{\circ}C$로 변화시킨 경우와 roasting 온도를 $130^{\circ}C$로 고정하고 roasting 시간을 5, 10, 20 및 30분으로 변화시킨 경우로 구분하여 행하였다. 상법 roasting은 $120^{\circ}C$에서 15분간 실시하였다. Methyl pyrazine 류의 함량과 함량비는 마이크로파 roasting 온도 및 rosting 시간에 영향을 받았으며 적정한 methyl pyrazine류의 비는 $140^{\circ}C$ 30분 roasting에서 얻을 수 있었다.

• 한국식품조리과학회지
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• 제31권5호
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• pp.534-543
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• 2015

Recently, the Tenebrio molitor larva was recognized as a novel food ingredient by the Ministry of Food and Drug Safety in Korea. Accordingly, we investigated its physical and sensory characteristics to establish the cooking conditions that may increase the demand of T. molitor larvae as a food. In this study, T. molitor larvae were cooked by various methods such as hot air dry, oven-broil, roast, pan fry, deep fry, boil, steam, and by microwave. In the physical evaluation of texture, the hardness and fracturability values were highest when larvae were cooked in the microwave. The adhesiveness, springiness, and chewiness values were highest when larvae were boiled. Boiled and steamed larvae had the highest lightness (L value), while oven-broiled larvae had the highest redness (a value) and yellowness (b value) values. Sensory evaluations assessed the appearance, aroma, flavor, and texture of cooked T. molitor larvae. Steamed and boiled larvae sizes were significantly large and the form was well preserved similar to fresh larvae. The moisture heat cooked (steamed and boiled) T. molitor larvae had the aroma and flavor of steamed corn, canned pupa, and boiled mushroom. In case of oven-broiled T. molitor larvae, the aroma and flavor of mealworm oil, seafood, sweet and roasted sesame were higher than in those cooked by other methods. In texture among sensory evaluation, the hardness and crispiness were the highest in the hot air dried and oven-broiled larvae, whereas juiciness was significantly higher in the boiled and steamed. Accordingly, we suggest that oven-broiled T. molitor larva will be prefered by consumer, due to its the rich aroma and flavor.

• 한국축산식품학회지
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• 제21권4호
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• pp.314-322
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• 2001

본 실험은 조리방법(Grilling, Pan-frying, Oven-roasting, Microwaving)에 따른 쇠고기 안심 스테이크의 이·화학적 변화를 조사하기 위하여 일반성분, pH, 근원섬유 소편화지수, 색도, 가열감량, 물성(Rheology) 및 관능검사(Panel test)를 실시하였다. 조리방법에 따른 일반 성분은 microwaving 방법에서 다른 조리방법에 비하여 낮은 수분함량과 높은 지방함량을 나타냈다. pH는 조리후 다소 상승하였으나 조리방법에 따른 pH 차이는 없었으며, 육색의 변화에 있어서 L*과 b* -값은 microwaving과 pan-frying방법에서 grilling이나 oven-roasting 방법에서 가장 낮게 나타났다. 조리방법에 따른 근원섬유 소편화도는 oven-roasting 방법에서 가장 높게 나타났으나 조리방법간의 유의적인 차이는 없었다. 가열감량은 microwaving 방법에 의한 조리육에서 가장 많았다. 조리육이 물성에 있어서 경도와 부서짐성은 다른 조리방법에 비하여 microwave oven을 이용한 조리방법에서 높게 나타났으며, 응집성은 microwaving 방법에서 가장 낮은 값을 나타냈다. 그러나 탄력성은 모든 조리방법들간에 유의적인 차이가 없는 것으로 나타났다. 관능검사에 있어서 grilling, pan-frying과 oven-roasting 방법은 우수한 것으로 평가되었으며, microwaving은 전 항목에서 가장 낮은 점수를 얻었다.

• 한국지하수토양환경학회지:지하수토양환경
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• 제18권1호
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• pp.67-77
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• 2013

To improve the energy efficiency of conventional thermal treatment, soil remediation with microwave has been studied. In this study, the remediation efficiency of contaminated soil with semi-volatile organic contaminants were evaluated with microwave oven and several additives such as water, formic acid, iron powder, sodium hydroxide (NaOH) solution, and activated carbon. For the experiment, loamy sand and sandy loam collected from Imjin river flood plain were intentionally contaminated with hexachlorobenzene and phenanthrene, respectively. The contaminated soils were treated with microwave facility and the mass removals of organic contaminants from soils were evaluated. Among additives that were added to increase the remediation efficiency, activated carbon and NaOH solution were more effective than water, iron powder, and formic acid. When 10 g of hexachlorobenzene (142.4 mg/kg-soil) or phenanthrene (2,138.8 mg/kg-soil) contaminated soil that mixed with 0.5 g iron powder, 0.5 g activated carbon and 1 ml 6.25 M NaOH solution were treated with microwave for 3 minutes, more than 95% of contaminants were removed. The degradation of hexachlorobenzene during microwave treatments with additives was confirmed by the detection of pentachlorobenzene and tetrachlorobenzene. Naphthalene and phenol were also detected as degradation products of phenanthrene during microwave treatment with additives. The results showed that adding a suitable amount of additives for microwave treatments fairly increased the efficiency of removing semi-volatile soil organic contaminants.