• Asian-Australasian Journal of Animal Sciences
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• v.30 no.6
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• pp.872-877
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• 2017

Objective: In order to utilize fat from broiler byproducts efficiently, it is necessary to develop an appropriate rendering procedure and establish quality information for the rendered fat. A study was therefore undertaken to evaluate the influence of rendering methods on the amounts and general properties of the fat recovered from broiler skin. Methods: The yield and quality of the broiler skin fat rendered through high and lower energy microwave rendering (3.6 W/g for 10 min and 2.4 W/g for 10 min for high power microwave rendering (HPMR) and high power microwave rendering (LPMR), respectively), oven baking (OB, at $180^{\circ}C$ for 40 min), and water cooking (WC, boiling for 40 min) were compared. Results: Microwave-rendered skin exhibited the highest yields and fat recovery rates, followed by OB, and WC fats (p<0.05). HPMR fat had the highest $L^{\star}$, $a^{\star}$, and $b^{\star}$ values, whereas WC fat had the highest moisture content, acid values, and thiobarbituric acid (TBA) values (p<0.05). There was no significant difference in the acid value, peroxide value, and TBA values between HPMR and LPMR fats. Conclusion: Microwave rendering at a power level of 3.6 W/g for 10 min is suggested base on the yield and quality of chicken fat.

• Journal of the Korean Society of Food Science and Nutrition
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• v.36 no.1
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• pp.117-123
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• 2007

HPLC quantifications of fresh and cooked (steamed/microwaved) spinach, one of the most frequently consumed vegetables in foodservice operations, were carried out to determine carotenoids compositions. An S-3 $\mu$m C30 stationary phase for reversed-phase columns with diode-array detection was used to separate and quantify geometric isomers of provitamin A carotenoids in the fresh and cooked spinach. The carotenoids in fresh spinach were identified and quantified: Lutein (63.0%), $\beta$-carotene isomers (all-trans 29.6%, 9-cis 3.2%, 13-cis 1.8%, $\alpha$-carotene 0.4%, zeaxanthin 2.1%) and cryptoxanthin. Cryptoxanthin, detected in a trace amount in HPLC, was not quantified in this study. Lutein was little affected by cooking methods and frozen conditions. 9-cis and 13-cis-$\beta$-carotene isomers were major types formed during cooking. Cooking (steam/microwave) did not alter carotenoid profiles of the samples, but the amounts of carotenoids quantified were greater than those in the fresh samples. Heat treatment such as steaming increased total carotenoids contents, especially trans-$\beta$-carotene (p<0.05). The carotenoid contents of the frozen spinach increased even after the microwaved treatment (p<0.05). These increases were likely to result from the increased extraction efficiency and inactivation of enzymes capable of carotenoids degrading during the heat treatments.

• Journal of the East Asian Society of Dietary Life
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• v.19 no.4
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• pp.533-543
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• 2009

The objective of this study was to compare the differences of opinion, purchasing behavior, and recognition of food labeling and nutrition labeling of frozen processed food between employees and non-employees in the frozen food industry. The results of this survey study showed that the group working in the frozen food industry had a positive opinion of frozen processed food compared to the non-employee group who was not working in the food industry. The main reason for the positive opinion of frozen processed food was because it was convenient and easy to prepare while the main concern with consuming frozen processed food was that it was bad for one's health. The most popular menu was western style. Sixty one percent of employees in the frozen food industry preferred the microwave-cooking method, while only 37.9% of non-employees preferred the microwave-cooking method followed by cooking in boiling water (27.6%). There was a significant (p<0.001) difference in the preference of cooking method between these two groups. Most of the respondents considered 'taste' as the most important factor and 32.9% of the respondents selected 'sanitation/health' as the most serious concern for the consumption of frozen processed food. Both groups checked the food & nutrition label to verify the expiration date and the presence of food additives. The non-employee group recognized the need for nutritional information on total calorie, carbohydrate, protein, fat, saturated fat, cholesterol, minerals, vitamins, sodium, and fiber on the nutrition label of frozen processed food.

• Korean journal of food and cookery science
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• v.27 no.6
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• pp.713-721
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• 2011

Korean cabbage (Brassica campestris L.ssp.pekinensis) is one of the major cruciferous vegetables. Cruciferous vegetables contain a rare series of secondary metabolites of amino acids called glucosinolates, as well as carotenoids, tocopherol, vitamin C and fibers. This study evaluated the effect of common cooking methods (boiling, microwaving, steaming and frying) on the phytochemical content (lutein, ${\beta}$-carotene, ${\gamma}$-tocopherol, and ${\alpha}$-tocopherol), and total antioxidant capacity of Korean cabbages, determined by DPPH assay and ABTS assay. Boiling caused a decrease in carotenoids, lutein and tocopherols. Microwaving and steaming were relatively good cooking methods for maintaining lutein, ${\beta}$-carotene, ${\gamma}$-tocopherol, and ${\alpha}$-tocopherol. The overall results of this study demonstrate that some domestic cooking procedures, specifically microwave and steaming, increased the bioaccessibility of carotenoids and tocopherol, highlighting the positive role of the nutritional properties of Korean cabbage.

• Korean Journal of Microbiology
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• v.11 no.2
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• pp.101-106
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• 1973

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.

• The Korean Journal of Food And Nutrition
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• v.14 no.6
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• pp.573-578
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• 2001

Cholesterol oxidation products(COPs) such as 7-ketocholesterol, 7 ${\alpha}$, 7 ${\beta}$-hydroxycholesterol and 25-hydroxycholesterol were analyzed for ensuring the safety of squid during its drying and cooking. In addition. changes of malonaldehyde in squid during its drying and cooking were also investigated. Cholesterol was detected 636.4m9/1009 in fresh sample, which was decreased during its drying and cholesterol contents in dried sample were 468.9mg/100g, 486.8mg/100g, respectively, while COPs contents of sun and hot air dried samples increased about 6.2 times more than those contents of fresh sample. Regardless of cooking methods, the contents of COPs in dried products increased after cooking. Especially, those contents were determined 127.3 mg/g in sun dried samples were cooked by microwave oven. The malonaldehyde contents of dried products increased after cooking, its contents in cooked samples by an microwave oven after sun dried were about 4.3 times more than in control products. In general, a small quantity of COPs were formed in dried samples which were cooked by a steam.

• Food Science of Animal Resources
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• v.33 no.6
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• pp.723-729
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• 2013

In this study, the quality characteristics due to the influence of various thawing methods on electro-magnetic and air blast frozen beef were examined. The loin and round of second grade Hanwoo were sliced into 5-7 cm thickness and packed with aerobic packaging. The packaged beef samples, which were frozen by air blast freezing at $-45^{\circ}C$ and electro-magnetic freezing at $-55^{\circ}C$, were thawed by 4 thawing methods with refrigeration ($4{\pm}1^{\circ}C$), room temperature (RT, $25^{\circ}C$), cold water ($15^{\circ}C$), and microwave (2450 MHz). These samples were thawed to the point, which were core temperature reached $0^{\circ}C$. Analyses were carried out to determine drip and cooking loss, water holding capacity (WHC), moisture contents and sensory evaluation. Frozen beef thawed by microwave indicated a lower drip loss (0.66-2.01%) than the other thawing methods (0.80-2.50%). Cooking loss after electro-magnetic freezing indicated 52.0% by microwave thawing for round compared with 41.8% by refrigeration, 50.1% by RT, and 50.8% by cold water. WHC thawing by microwave with electro-magnetic freezing didn't showed any difference depending on the thawing methods, while moisture contents was higher thawing by microwave with electro-magnetic freezing than refrigeration (71.9%), RT (75.0%), and cold water (74.9%) for round. The texture of sensory evaluation for round thawed by microwave result was the highest than refrigeration (4.7 point), RT (6.4 point) and cold water (6.6 point), while sensory evaluation was no significant difference. Therefore, it was shown that microwave thawing is an appropriate way to reduce the deterioration of meat quality due to freezing.

• Korean Journal of Food Science and Technology
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• v.8 no.2
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• pp.80-84
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• 1976

Two varieties, Lasoda and Sebago potatoes, were studied. Different cooking methods, conventional oven baking at $218^{\circ}C$ and microwave oven baking, have been used to compare the retention of the phenolic compounds. Peeled cortex samples of fresh and cooked potatoes were analyzed for total phenols, phenolic constituents, and moisture loss. Phenolic content was higher in fresh potatoes than in cooked potatoes. Laasoda had higher phenolic content (3. 63mg) than Sebago (1. 71mg). Potatoes with higher phenols (Lasoda) also had larger quantities of chlorogenic acid. There was a greater moisture loss in conventional oven baking potatoes than in microware oven.

• Proceedings of the KIEE Conference
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• 2001.10a
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• pp.205-207
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• 2001

In response to this inverter microwave oven has been developed to improve high speed cooking time & energy saving performance. The voltage resonating inverter has a defect in switching element that works at 5 or 6times higher than input voltage. Especially, it is very difficult to choose the switching device is very high for the 220 (V) commercial voltage. In this paper, it is proposed the optimum method to realize the turbo 1200(W) output power for microwave oven that is employed the 900(V) IGBT with decreasing operating voltage of the switching component by making the 220(V), 1000(W) inverter through the active clamp voltage resonating inverter.

• Korean journal of food and cookery science
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• v.7 no.1
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• pp.53-59
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• 1991

The purpose of this study is to investigate textural characteristics of egg solution coagulated with steamer and microwave oven, and egg solution diluted various concentration of it with water or milk. Textural Characteristics of the samples were evaluated by the Sensory test and Rheometer. The results obstained were as follow; 1. Rheometer measurement indicated that the thicker is concentration of egg solution, the harder is samples 2. In sensory evaluation on the various concentration of egg solution, the panels on the overall quality showed the most favorite tendency that the sample diluted with 50% of water and the one with 70% of milk in use steamer; the sample diluted with 30% of water and the one with 70% of milk in use microwave oven.