• Korean Journal of Food Science and Technology
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• v.30 no.3
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• pp.569-573
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• 1998

This study was conducted to investigate the differences of textural characteristics and microstructure of sugared chestnuts between heated by a heater and microwave. Raw chestnuts were boiled and infiltrated the sugar in sugar syrup by heating. The content of WSP (water soluble pectin) was increased, but HSP (hydrochloric acid soluble pectin) was decreased by boiling and sugaring. This change was remarkable when it was boiled and sugared by a microwave heating. The hardness, gumminess and chewiness were more decreased in the sugared chestnut boiled and sugared with a microwave than that processed with a heater. Microstructure of sugared chestnut processed with a microwave heating showed the distruction of cell wall.

• Food Science of Animal Resources
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• v.18 no.3
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• pp.269-275
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• 1998

The purpose of this study was to determine the thermal inactivation of Salmonella enteritidis, Salmonella typhimurium and E. coli O111 in liquid cultures treated with microwave energy. Furthermore, this study was to introduce new methodologies for studying nonthermal microwave effects on microorganisms, using controlled microwave energy and specially designed apparatuses. For the automatic temperature control during microwave heating, the real time data acquisition and computation system is designed with BASIC routine. The automatic temperature control system used in the experiments perform relatively stable control at the experiment temperature of 45, 50, 55 60$^{\circ}C$ and 65$^{\circ}C$ for 30 minutes. The effects of microwave heating on liquid cultures was compared with that of conventional heating, still reduces effectively the number of pathogenic bacteria in liquid cultures. While no particular differences between microwave heating and conventional heating was observed in the activation of E. coli at 45$^{\circ}C$ test, the activation of Sal. enteritidis and Sal. typhimurium was slightly reduced during the microwave treatments.

• Journal of the Korean Society of Food Science and Nutrition
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• v.30 no.6
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• pp.1026-1032
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• 2001

Microwave treatment was studied to investigate the antioxidant ability of rice hull and rice bran. The color changes were related to the intensity of microwave and to the treated time on rice bran. However, the electron donating abilities of rice hull and rice bran extract were not much affected by microwave intensity. Rice hull extract treated with a 100 W microwave showed 80% inhibition of lipid peroxidation when fish oil was treated with $H_2O$$_2$. Also inhibition activity against lipid peroxidation in rice hull is more stable than that of rice bran when treated with microwave. Overall, rice hull extract showed better antioxidant activity than rice bran. It seems that rice hull contains higher antioxidant components as well as the browning reaction products having anti-oxidant activity during microwave treatment.

• Mass Spectrometry Letters
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• v.2 no.4
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• pp.84-87
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• 2011

The effectiveness of microwave-assisted protein digestion in different well positions of a 96-well microplate was investigated where microwave-assisted protein digestion of bovine serum albumin was performed in 10 different wells of a 96-well microplate in a microwave oven. Similarly increased sequence coverages (~70%) were generally observed for the 10 microwave-assisted protein digestion samples compared to conventional overnight digestion (63%), which is possibly due to higher miscleavage ratios (~53%) of the samples from microwave-assisted protein digestion than conventional overnight digestion (42.1%). The reproducible results of microwave-assisted digestions from different well positions demonstrate the potential of high-throughput analysis of proteins using microwave-assisted protein digestion.

• Bulletin of the Korean Chemical Society
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• v.28 no.12
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• pp.2338-2343
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• 2007

Under the framework of green chemistry, an efficient and extremely fast procedure for the synthesis of 5a-h through four-step procedure starting from 2-arylidenetetralin-1-one 1a-d under microwave irradiation is described. A considerable increase in the reaction rate has been observed with better yield. The structures of the synthesized compounds have been characterized on the basis of their elemental analysis and spectral data. Synthesized compounds 5a-h was evaluated for their antimicrobial activity. Some of the compounds exhibited appreciable activity.

• Journal of the Korean Society of Food Science and Nutrition
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• v.25 no.3
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• pp.504-512
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• 1996

Changes in quality of cooked rice after microwave reheating were evaluated. Ceramic coated microwave oven reduced a reheating time(1 min). Storage temperature, storage time and microwave reheating did not affect the color value of cooked rice after microwave reheating. Hardness of cooked rice after microwave reheating decreased in frozen storage treatment. Photomicrographs of cross-section of cooked rice after microwave reheating showed restoration of starch. Effect of storage temperature and time were not significant in appearance, aroma, taste and texture of cooked rice after microwave reheating for sensory evaluation test.

• Korean Journal of Food Science and Technology
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• v.35 no.2
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• pp.222-228
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• 2003

Optimum extraction conditions for yield, browning color, electron-donating ability, nitrite-scavenging effect, total polyphenol content, and tyrosinase-inhibitory activity of Flammulina velutipes were determined using response surface methodology through central composite design. Yield of F. velutipes was affected by ethanol concentration, and browning color improved more with the increase of ethanol concentration than microwave power. Nitrite-scavenging effect was improved with increasing ethanol concentration and decreasing microwave power. Electron-donating ability and total polyphenol content were improved with increasing ethanol concentration and microwave power. Tyrosinase-inhibitory effect increased more with decrease in microwave power than with ethanol concentration. The optimal range of extraction conditions for effective component of F. velutipes were $47.21{\sim}76.05$ watt of microwave power, $10.25{\sim}43.56%$ of ethanol concentration, and 5.72 min of extraction time.

• Food Science and Preservation
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• v.16 no.5
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• pp.669-674
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• 2009

We prepared puffed instant Nuroong-gi samples using a microwave and investigated the physicochemical characteristics of the products. The quality of Nuroong-gi prepared using a microwave was compared with that of noodles prepared in a steam cooker and pressure cooker in terms of moisture content, color, water binding capacity ratio, viscosity, sedimented volume of insoluble solids, turbidity, and sensory evaluation. The moisture content of Nuroong-gi prepared in a microwave was similar to that of steam cooker and pressure cooker samples. The color (lightness) of steam cooker-prepared noodles was greater than that of noodles cooked using other modes. The water binding capacity ratio fell with increasing microwave cooking time. The viscosity of noodles prepared using a microwave was higher than that of pressure cooker samples and lower than that of steam cooker noodles. The sedimented volume of insoluble solids and turbidity increased with a rise in cooking temperature. Nuroong-gi prepared in a microwave scored higher in sensory evaluation tests than did steam cooker or pressure cooker samples. These results indicate that Nuroong-gi preparation using a microwave is very efficient.

• Applied Biological Chemistry
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• v.44 no.4
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• pp.235-239
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• 2001

Effect of microwave treatment to barley bran was tested on antioxidative ability. Treatments of microwave at 100 W and 200 W, changed color of barley bran to brown, but carbonation was happening at 440 W. The electron donating abilities of barley bran was not reduced when treated with 100 W and 200 W microwave treatment for 10 minute. According to TBARS, the barley bran extract treated with 100 W and 200 W intensity of microwave for 10 min maintained the inhibition of lipid peroxidation, while the extract from 440 W microwave treatment for 5 min did not. Total phenolic contents were reduced with increased intensity of microwave treatment. The antioxidant activity of barley bran was not affected by microwave treatment at 100 W and 200 W, while the 440w microwave treatment reduced the activity due to carbonation of barley bran and decreased phenolic compounds.

• Korean Journal of Food Science and Technology
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• v.31 no.1
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• pp.54-61
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• 1999

A study was conducted to find a rapid thawing method which prevents excessive drip loss and local overheating. Effects of thawing methods (conventional thawing vs. 2,450 and 915 MHz microwave thawing) on thawing time, temperature profile, drip loss, water holding capacity, total color difference and total aerobes were investigated. Samples were thawed at 4, 28 and $50^{\circ}C$ in a refrigerator or an oven for the conventional thawing methods the convertional thawing methods. Power levels of 5, 10 and 15 kW were used for 915MHz microwave thawing. Cotreatment of 915 MHz microwave and convectional heating $(120^{\circ}C)$ was tested. 915 MHz microwave accelerated the thawing rate, and showed significant effects on penetration depth, drip loss, water holding capacity and total aerobes. Cotreatment of 915 MHz microwave and convection heating was appeared to be a suitable thawing process for the food industry.