• Korean Journal of Food Science and Technology
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• v.31 no.3
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• pp.631-637
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• 1999

An investigation was carried out to study the effects of aging time, storage temperature, and drying type on the physical, chemical and sensory properties of Korean rice cake. Water content and cooking properties were significantly influenced by aging time and storage temperature. However, aging time did not affect the soup turbidity. Difference in water content was noticeable by drying type. The microwave treated rice cake (MW) showed a higher water content than the other ones. The lightness (L-value) was not affected by the aging time and drying type. Rice cake storaged at 4oC showed the highest L-value. The textural properties of rice cake were influenced by the all sources of variables. There was a significant difference in hardness between microwave and hot air treated rice cake (MWH), and microwave and vacuum treated rice cake (MWV). In the sensory properties, mean intensities of all attributes except chewiness were significantly different among drying types. The MWV showed a higher acceptability than the MW and the MWH. Scanning electron photomicrographs revealed that the MWV has more porous structure. The MWV was the most desirable one as determined by the physical, chemical and sensory evaluation.

• Applied Chemistry for Engineering
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• v.31 no.2
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• pp.172-178
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• 2020

In this study, the optimization of the biodiesel production process from waste oil using microwave with response surface methodology (RSM) was conducted. The microwave irradiation time and power in addition to the alcohol/oil mole ratio were chosen as process parameters. Also the fatty acid methyl ester (FAME) content (over 96.5%) and kinematic viscosity (1.9~5.5 cSt) were selected as response values. From basic experiments, the range of quantitative factors were set as following; 4~6 min, 400~600 W, and 7~9 for the microwave irradiation time and power, and alcohol/oil molar ratio, respectively. The optimum conditions for the methanolysis were 5.0~5.1 min, 481.3~525.5 W, 7.9~8.4, and 2.0 or 3.0 mg KOH/g for the microwave irradiation time and power, methanol/oil molar ratio, and each acid value, respectively. The FAME content and kinematic viscosity were predicted as 97.49~96.34% and 4.01~4.12 cSt, respectively, under the condition above. Under the optimum experimental conditions, the results showed that the FAME content and kinematic viscosity of 97.82~96.42% and 4.07~4.16 cSt, respectively were measured and the mean error rates were 0.22% and 0.98%, respectively.

• 유체기계공업학회:학술대회논문집
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• 2002.12a
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• pp.123-128
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• 2002

Over the range(OTR) has been applied for cooking and ventilation functions especially in northern Amarica. Because flow rate and operating rpm of the double sided sirocco fan for ventilation are much higher and than the microwave oven system, the major noise source is the sirocco fm. Recently, the quiet fan development is one of very important issues for amenity. In this study, the noise source identification using multi-microphone array system was carefully carried out and numerical simulations for understanding the aerodynamic and aeroacoustic of the fan were peformed. The sound level of tonal noise is predicted with a good accuracy but that of the broadband shows some discrepancy. In order to reduce the broadband noise, the inlet region of sirocco fan have to be modified that the secondary flow should be suppressed. Based on these results, new low noise fan and OTR is now developing.

• Korean journal of food and cookery science
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• v.10 no.2
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• pp.111-120
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• 1994

본 실험은 4가지의 다른 무게를 가진 고기(0.1kg,0.5kg, 1kg, 1.5kg)를, 3가지의 다른 출력의 전자파(40%, 60%, 100%)로 조리시 나타나는 조리조건(오븐의 효율성, 대기시간, 대기시 상승온도)과 물리 화학적인변화(수분, 단백질, 지방, vit B$_1$,의 함량, 콜라겐의 용해도, 보수력, texture)를 관찰하였다. 고기의 무게가 증가할수록 전자렌지의 효율성은 낮아졌으며, 단위 무게당 조리시간은 고기의 무게가 증가할수록 길어졌다. 화학적 성분들에 있어서는 지방과 콜라겐의 용해도를 제외하고는 처리구간에 유의적인 차이를 보이지 않았다. 지방과 콜라겐의 용해도는 전자파의 출력차이에 의한 유의적인 차이는 나타나지 않았으나, 고기 무게가 증가할수록 지방의 함량의 증가와 콜라겐의 용해도는 증가하였다. Texture를 측정한 항목들에 대해서는 고기의 무게에 따른 유의적인 차이는 나타나지 않았으나 전자파의 출력에 의한 차이를 나타내었다.

• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 2003.11a
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• pp.368-371
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• 2003

The humidity sensors with a stable characteristics and gas sensors operating at room temperature have been fabricated, and a multi-functional sensor system which has gas sensor, humidity sensor, temperature sensor and control circuit has been applied to the microwave oven system. For a suitable cooking state, the humidity sensors was more applicable to heating and defrosting condition than gas sensors, however, the dynamic characteristics of gas sensors were obtained in the easy burning food such as pop corn.

• Journal of the Korean Society of Food Science and Nutrition
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• v.26 no.6
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• pp.1221-1227
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• 1997

To measure nutritional components and physical quality of Wanja-jeon(Korean pan fried meat balls)was investigated during storage in a simulated hospital cook/chill foodservice system. The Wanja-jeon was cooked and stored for 4 weeks in chill conditions of 2 and 7$^{\circ}C$ and then reheated in the microwave oven. Moisture, protein, and fat contents were decreased little during 4 weeks storage at 2 and 7$^{\circ}C$. Total unsaturated fatty acids(TUFA) and polyunsaturated fatty acids(PUFA) increased slightly at 7$^{\circ}C$ storage. Total free amino acid contents were reduced after 4 weeks of storage, while total amino acids were affected little during chilled storage. However, volatile basic nitrogen(VBN) increased during the 4 weeks storage from 11.2mg%, immediately after cooking, to 14.1~14.2mg%. After reheating, thiobarbituric acid(TBA) value increased more significantly to 0.19 and 0.20.

• Korean journal of food and cookery science
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• v.9 no.1
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• pp.1-6
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• 1993

The possession of microwave range, oven and oven-microwave range has been greatly increased with 88 Seoul Olympic Game as a momentum, and the possession rate was by 68%. The respondent answered the function of microwave range to be more necessary than that of oven, and the two household commodities have been mostly used to reheat and heat simply prepared frozen foods. The 35% among total respondent wished to cook the prepared frozen foods like pizza, but the 87% prefered to cook bakery. The frequencies of the use of oven were 35%, 35% for cooking premix and raw materials, and 20%, 20% for cooking half-prepared and prepared foods, respectively. The respondent of 39% was interested in premix foods as a future preference for food forms, and the respondent with interest in half-prepared food was 30%, but the preference for raw materials and prepared foods showed a trend to be decreased. The respondent of 60ft had eaten out six times week, and 50% had eaten instant and fast foods 1~3 times week. As the results of this survey, most of consumers prefer to more convenient foods. Therefore, it is expected that the function of oven and microwave range would be widely useful if various foods are improved with regards to convenience for use and preference.

• Journal of the Korean Society of Food Science and Nutrition
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• v.45 no.8
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• pp.1221-1226
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• 2016

This study investigated changes in the S-allyl-L-cysteine (SAC) content of garlic using different cooking methods. Methods for determining SAC were validated by determining specificity, linearity, limit of detection (LOD), limit of quantification (LOQ), precision, and accuracy using an high-performance liquid chromatography-fluorescence detection system. Results showed high linearity in the calibration curve with a coefficient of correlation ($R^2$) of 0.9999. The LOD and LOQ values for SAC were 0.15 and $0.47{\mu}g/mL$, respectively. The relative standard deviations for intra- and inter-day precision of SAC were less than 5%. The recovery rate of SAC was in the range from 97.35% to 97.47%. The SAC content of raw garlic was 2.77 mg/g, and there was no significant difference in SAC content according to blanching and microwave treatment. However, SAC content upon boiling and autoclaving at $110^{\circ}C$ and $121^{\circ}C$ increased from 3.50~9.16 mg/g, 6.52~16.21 mg/g, and 14.15~50.24 mg/g with increasing cooking temperature and time, respectively.

• Journal of Food Hygiene and Safety
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• v.12 no.3
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• pp.240-253
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• 1997

The main problems contributing to food poisoning outbreaks in institutional settings and a home were reviewed and analyzed through the epidemiological investigations of food poisoning. The major documented factors included improper holding temperatures, inadequate cooking, poor personal hygiene, cross-contamination and contaminated equipment, food from unsafe sources, failure to follow food hygiene policies, and lack of education, training, monitoring and superivision. Usually more than one factor contributed to the development of an outbreak. (1) Use of improper holding temperatures was the single most important factor contributing to food poisoning. They included improper cooling, allowing a laps of time (12 hours or more) between preparing food and eating it, improper hot holding, and inadequate or improper thawing. Food thermometers were not used in most of the instances. (2) In inadequate cooking, the core temperature of food during and after cooking had not been measured, and routine monitoring was limited to recording the temperature of plated meals. Compared with conventional methods of cooking, microwave ovens did not protect against food poisoning as effectively. Centralized food preparation potentially increased the risk of food poisoning outbreaks. (3) Poor personal hygiene both at the individual level (improper handwashing and lack of proper hygienic practices) and at the institutional level (poor general sanitization) increased the risk of transmission. Person to person transmission of enteric pathogens through direct contact and via fomites has been noted in several instances. (4) Obtaining food from unsafe sources was a risk factor in outbreaks of food poisoning. Food risks were high when food was grown or harvested from contaminated areas. Possibilities included contamination in the field, in transport, at the retail site, or at the time it was prepared for serving. (5) Cross-contamination and inadequate cleaning/handling of equipment became potential vehicles of food poisoning. Failure to separate cooked food from raw food was also a risk factor. (6) Failure to follow food hygiene policies also provided opportunities for outbreaks of food poisoning. It included improper hygienic practices during food preparation, neglect of personnel policies (involvement of symptomatic workers in food preparation), poor results on routine inspections, and disregarding the results and recommendations of an inspection. (7) Lack of formal and in-service education, training, monitoring, and supervision of food handlers or supervisors were critical and perhaps neglected elements in occurrences of food poisoning.

• The Korean Journal of Community Living Science
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• v.28 no.4
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• pp.525-535
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• 2017

The purpose of this study was to compare the of ash and minerals contents in different types of soybeans (Baektae, Seoritae, Heuk Tae and Seomoktae) with different cooking methods. Raw, boiled and pan-fried soybean samples were prepared by the Rural Development Administration. Samples were digested by using a microwave and analyzed using ICP-OES and ICP-MS for determining the ash and minerals contents. Ash content in four raw soybeans ranged from 5.07 to 5.59 g/100g. There was no significant difference in the ash contents in raw and pan-fried soybeans (p>0.05). However, the ash content of boiled soybeans was 9 to 14% lower than that of raw soybeans (p<0.05). The minerals contents of Baektae and Seomoktae were high and the major minerals of various soybeans were K, P, Mg, and Ca, which accounted for ash 60.80-65.61%, 20.73-24.26%, 6.90-8.46% and 5.79-8.60%, respectively. The mineral contents of soybeans were significantly different depending on the type of cultivar (p<0.05), but the tendency was not constant. Because the process of soaking and boiling of soybeans made the soluble minerals elute, the ash and mineral contents were reduced. And process of pan-frying of soybeans make Because process of soaking and boiling of soybeans make soluble minerals elute (Ed- this section is very confused and seems to have 2 sentences combined: please check your intended meaning), the ash and mineral contents were reduced. As the soybeans are cooked by pan-frying, the water in the soybeans is evaporated and the mineral content is concentrated or kept constant. These results can serve as the basic data of mineral content during processing and cooking of soybeans.