• Korean journal of food and cookery science
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• v.22 no.3 s.93
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• pp.402-417
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• 2006

Research interest on functional food and phytochemicals has mainly focused on their health effects, mechanism of action and structure-activity relationship for the development of nutraceuticals. Considering the intake of phytochemicals via the normal diet, further information is required on changes in food functionality or individual phytochemicals that occur during the cooking or processing of foods, in order to increase the intake of these bioactive compounds, because many of the unit-operating procedures involved in cooking or food processing may result in physicochemical changes of food constituents. This study reviews the changes of selected phytochemicals, i.e. flavonoids, organosulfur compounds and carotenoids, or food functionality by major cooking or processing procedures such as heating, fermentation, and pH changes. In general, heating has a negative effect on food functionality, although in some cases, mild heating increases bioactive phytochemical contents. Some phytochemicals, including anthocyanins and catechins, are stabilized in lower pH conditions. The structures of phytochemicals, including isoflavones and catechins, are changed by fermentation. The loss of bioactive compounds may be decreased by recently developed cooking or processing methods such as microwave cooking or use of high hydrostatic pressure. However, the effects of cooking and processing procedures on food functionality and phytochemicals are so diverse and dependent on test conditions that further research efforts are needed to form accurate conclusions on the effects of cooking and processing of foods.

• Korean Journal of Microbiology
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• v.18 no.3
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• pp.148-152
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• 1980

The microwave of 2450 MHz, generated by a household cooking oven, was evaluated for its applicability to melt various rehydrated media and to remove dissolved oxygen from tubed media for anaerobic culture. The effect on the sterilization of E. coli in selective media was also evaluated. The following results were obtained. 10 The microwave oven was useful in saving time for melting media and in eliminating heat and combustion gas from the laboratory, which were inevitable by-products in the conventional flame method. 2) Dissolved oxygen could be removed without boiling over by exposing the tubes of anaerobic culture medium after putting them in a wire basket in a beaker with water. 30 The count of E. coli during the melting of MacConkey and EMB agar were similar to those treated with open flame. The microwave treatment was not considered a possible mean to replace autoclaving even in these selective media.

• 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.

• Korean Journal of Food Science and Technology
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• v.39 no.5
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• pp.500-505
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• 2007

The objective of this study was to investigate the effects of cooking methods (cooking apparatus and reaction level of oxygen) on the rancidity, reactive oxygen species (ROS), and furans produced while cooking deep-fired instant noodles. The sample rancidities showed a decreasing trend regardless of the cooking apparatus, as the available oxygen content in the cooking pot was reduced. In particular, soaking and then cooking using a microwave oven was found to be the most effective method to retard rancidity development. The ROS concentration after cooking had a similar trend to the rancidity. The furan concentrations of the samples significantly decreased under all cooking conditions as compared to the control, and the lowest value was 10.69 ppb for the sample cooked in a microwave oven without a cooking pot lid after soaking. The results indicate that cooking in a microwave oven with soaking was the most effective method for the oxidative stability of deep-fried instant noodles.

• Korean Journal of Human Ecology
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• v.7 no.1
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• pp.21-31
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• 2004

This study was carried out to investigate the physico-chemical properties during the rib-eye preperation while cooked rib-eye and fine sensory evaluation by various cooked utensil (oven, fry-pan and microwave). 1) Change of moisture contents of sauce-pan boiling cooker was lower than boiling by preasure cooker and fat content of sauce-pan boiling was higher than preasure cooker boiling. 2) Degree of cholesterol of cooker meat was not change for content of cholesterol during the boiling preperation but progressively decreased in order of well-done steak < medium steak < rare steak measured by cholesterol analysis. 3) Sensory evaluation conducted by fine graduate as panelists showed that oven steak and fry-pan steak had higher score of sensory evaluation. While microwave steak had the lowest score all sensory profile score.

• Journal of Food Hygiene and Safety
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• v.11 no.1
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• pp.1-5
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• 1996

This study is performed to identify the contents of nitrosamine in meat (beef, pork) and meat product (ham, bacon, sausage) by gas chromatograph-thermal energy analyzer. The author also determained the formation of nitrosamine in these products when they were cooked in frying pan at 21$0^{\circ}C$ for 4 minutes and microwave for 45 and 75 seconds. N-ni-trosodimethylamine (NDMA) analysis was impossible in the most products because of their impurieties. On the other hand, N-nitrosopyrrolidine (NPYR) of 0~9.4 ug/kg in meat and 0~15.6 ug/kg in meat products were detected, respectively. When meat and meat products were cooked, generally contents of NDMA and NPYR have a tendency to be increased a little. Meat and product being cooked in microwave rather than frying pan, contents of NDMA and NPYR were detected more. Especially, in sausage contained much flsh, contents of NDMA was detected more.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.45 no.4
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• pp.317-327
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• 2012

The changes in the proximate compositions, lipid classes, and fatty acids of muscle and dripped lipids, and the amino acid compositions and mineral content were studied in Spanish mackerel Scomberomorus niphonius muscle cooked using a frying pan, oven, and microwave oven. The moisture content was high in the raw sample (65.7%) and decreased with cooking, decreasing the most with frying pan method (54.5%). Conversely, the protein, lipid and ash contents increased significantly with cooking (P<0.05). The dripped lipid content from the cooked muscles was the highest with the frying pan sample (0.81%) and was approximately half this level in the oven (0.46%) and microwave oven (0.34%) samples. The percentage of non-polar lipid (NL) in the total lipid content exceeded 95% for the muscle lipids (13.9-17.6 g/100 g sample) and 99% for the dripped lipids (0.34-0.81 g/100 g sample). The prominent fatty acids were 18:1n-9, 16:0, 22:6n-3, 16:1n-7, and 20:5n-3 in the muscle and dripped lipids. The frying pan muscle lipid contained high levels of saturates and monoenes such as 16:0, 18:0, and 18:1n-9, and low levels of polyenes compared with other muscle lipids. The fatty acid compositions of the dripped lipids were similar with all three cooking methods. The prominent total amino acids in Spanish mackerel muscle were glutamic acid, aspartic acid, lysine, leucine, and arginine, and their proportions were similar (45.49-45.82%) in all samples. The potassium and phosphorous contents increased significantly with cooking (P<0.05), and while no heavy metals were detected in any sample. These results indicate that the change in nutritional components, especially the lipid content, was lower with the microwave oven and oven methods compared with the frying pan method.

• 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.

• Asian-Australasian Journal of Animal Sciences
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• v.29 no.1
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• pp.100-108
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• 2016

In this study, a survey was conducted to both evaluate the consumers' general attitudes for purchasing and storing the raw chicken and determine the thawing practices used for defrosting frozen chicken at home. About 75% of the consumers indicated purchasing chicken meat at least once a week or more. Furthermore, the majority (82.16%) of those who stored at least a portion of the raw chicken stated freezing the raw chicken meat at home. Freezing the chicken meat was considered to have no effect on the quality by 43.49% of the consumers while 56.51% thought that freezing had either negative or positive effects on the quality. The survey study indicated that top five most commonly used thawing practices included thawing on the kitchen counter, thawing in the refrigerator, thawing in the warm water, thawing in the microwave, and thawing under tap water. In addition, an experimental study was conducted to determine the effects of these most commonly used thawing practices on some quality characteristics of the chicken meat including pH, drip loss, cooking loss, color analysis and textural profile analysis. Although, $L^*$ value for thawing on the kitchen counter was the lowest, after cooking, none of the thawing treatments have a significant effect on the color values. Thawing in the microwave produced the highest drip loss of 3.47% while the lowest drip loss of 0.62% was observed with thawing in the refrigerator. On the other hand, thawing in the microwave and refrigerator caused the lowest cooking loss values of 18.29% and 18.53%, respectively. Nevertheless, there were no significant differences among textural parameter values of the defrosted and then cooked samples using the home based thawing practices, indicating similar quality characteristics among the samples.

• Journal of the East Asian Society of Dietary Life
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• v.16 no.5
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• pp.578-584
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• 2006

This research analyzed the contents of ascorbic acid according to cultivating season, regions and cooking method. The ascorbic acid content was steadily increased from 40.08 mg per 100 g on the 5th days after blooming to 90 mg on the 30th day, an increase of 2.25-fold. The ascorbic acid content of the peppers was highest for (C) region at 100.9 mg per 100 g, followed by (B) region at 90 mg and (A), region at 23.35 mg. it increased by ascending downward from the stem. If examining species' and regional ascorbic acid change of marketing peppers, it was contained in flesh most and placenta, seed in order in four species. The ascorbic acid content of the peppers was affected by the cooking method and decreased greatly in the order of blank>microwave>$saut{\acute{e}}ing$> boiling> steaming.