• Journal of Distribution Science
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• v.16 no.2
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• pp.53-65
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• 2018

Purpose - The purpose of this study is to investigate the effect of gamma - irradiation on the effluent from food distribution in the large agricultural and marine products market. This study will contribute to the distribution process as well as the agricultural and fishery distribution facilities. Research design, data, and methodology - In order to reduce the odor, the smell was examined in the anaerobic digestion process by irradiating gamma rays to the wastewater of mixed food discharged from a large restaurant. An odor determination panel list was constructed to determine if the odor was present in the air dilution drainage and the odor concentration was analyzed by instrumental analysis. Results - It was confirmed that the sulfur content increased gradually from 3 months. Ammonia decreased from 33.57ppm at the initial measurement to 4.12 ppm at the end of the experiment. Methane production was highest at 100kGy when exposed to gamma rays of 0-200kGy at pH 12. In other words, it is considered that gamma irradiation doses are most effective at 100kGy and are suitable for large capacity wastewater treatment facilities in terms of economic feasibility. Conclusions - In pre-treatment of compound food wastewater, gamma irradiation is most cost effective when examined at 100kGy. The economic efficiency of the pre-treatment method by gamma irradiation is much higher than the wastewater treatment in the large-scale agricultural and marine products distribution market.

• Journal of Food Hygiene and Safety
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• v.1 no.2
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• pp.133-141
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• 1986

Gamma irradiation as a new physical treatment was applied to comparative researches with a conventional chemical fumigant on the microbiologicai and physicochemical qualities of selected agricultural products such as powdered hot pepper soybean paste,. oyste.mushroom powder, carrot flake, and raw sesame. The microorganisms contaminated in the sample, including total bacteria, thermophiles, acid tolerant bacteria, fungi, osmophilic molds and coliforms were sterilized with irradiation doses of 7-10 kGy, while ethylene oxide (E.O) fumigation proved insufficient for the destruction of them. An optimum dose of irradiation was less detrimental than E.O. fumigation to the physicochemical properties of the sample. Sensory evaluation after three months of storage at room temperatures showed that the overall acceptability of irradiated sample was higher than that of the non treated control as well as E.O. fumigated samples.

• Proceedings of the Korean Society of Postharvest Science and Technology of Agricultural Products Conference
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• 2003.10a
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• pp.135.1-135
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• 2003

To elucidate the effect of gamma-irradiation on the molecular properties of hemoglobin, the secondary, tertiary structure, and the molecular weight size of the protein were examined after irradiation at 0.5, 1, 5, and 10 kGy. Gamma-irradiation of hemoglobin solutions caused the disruption of the ordered structure of the protein molecules, as well as degradation, cross-linking, and aggregation of the polypeptide chains. A SDS-PAGE study indicated that irradiation caused initial fragmentation of the proteins and subsequent aggregation due to cross-linking of the protein molecules. The effect of irradiation on the protein was more significant at lower protein concentrations. Ascorbic acid decreased the degradation and aggregation of proteins by scavenging oxygen radicals that were produced by irradiation. A circular dichroism study showed that irradiation decreased the helical content of hemoglobin with a concurrent increase of the aperiodic structure content. Fluorescence spectroscopy indicated that irradiation decreased the emission intensity that was excited at 280 nm.

• Proceedings of the Korean Society of Postharvest Science and Technology of Agricultural Products Conference
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• 1997.04a
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• pp.40-40
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• 1997

• Proceedings of the Korean Society of Postharvest Science and Technology of Agricultural Products Conference
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• 1994.07a
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• pp.9-12
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• 1994

• Proceedings of the Korean Society of Postharvest Science and Technology of Agricultural Products Conference
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• 2002.08a
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• pp.178.2-179
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• 2002

• Journal of Microbiology and Biotechnology
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• v.11 no.2
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• pp.342-345
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• 2001

A bacterial strain PH-4, which produces an enzyme catalyzing the degradation of crosslinked poly(${\gamma}$-glutamic acid) hydrogels, was isolated and identified as a Flavobacterium sp. The enzyme was obtained by the sonication of the bacterial cells preincubated in a Bouillon medium with shaking, without adding of poly(${\gamma}$-glutamic acid) as an inducer. The products of the hydrogel degraded by the crude enzyme agreed closely with the depolymerized materials in SDS-polyacrylamide gel electrophoresis using methylene blue staining, and with a glutamic acid monomer on thin-layer chromatography, thereby suggesting that strain PH-4 produced a kind of exohydrolase.

• Macromolecular Research
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• v.13 no.4
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• pp.339-343
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• 2005

Microbial hydrogel was prepared by ${\gamma}-irradiation$ of poly(${\gamma}-glutamic acid$) (PGA) which was produced from Bacillus subtilis BS 62 and it's physico-chemical characteristic was examined. The hydrogel, prepared from 10% PGA with the dose of 48 kGy, was swollen up to 1,370 times of specific water content as dry weight basis. The hydrogels obtained above the dose of 48 kGy appeared to have higher compressive strength but lower specific water content. The period to reach a swelling equilibrium for the hydrogel in deionized water at the temperature range of 4 to $45^{\circ}C$ was about 10 h. The swollen hydrogel was shrunk in ionic solutions with the increase of ionic strength, and the rate of shrinkage was greater in calcium chloride solution than in sodium chloride. Specific water content of the hydrogel was quickly decreased at $80^{\circ}C$, showing a thennally hydrodegradable property.

• Preventive Nutrition and Food Science
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• v.3 no.3
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• pp.295-301
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• 1998

Potential applications of irradiation technology inpostharvest handling of agricultural products have been documented over the past five decades. The biological effects of ionizing radiation on food were demonstrated to have the potential both of reducing the storage losses by controlling spoilage microoraganisms, insects, to have the potential both of reducing the storge losses by controlling spoiliage microorganisms, insects, sprouting and ripening, and of improving the hygienic quality of raw and processed products. Food irradiation is recognized as a physical and cold process using gamma-rays from radioisotope sources and electron-beam from the accelerator. As one of the technologies or techniques for preserving and improving the safety of food, irradiated technology has been approved in some 40 countries for more than 200 individeual items of foods and of these about 30 countries including Korea are commerically utilizing this technology. Although limited quantities of irradiated foods are available in the market now, the proper uses of this renewed technology will offer great possibilities not only for increasing the availability of postharvest agricultural products, thereby contributing to price stabilization in the off-season, but also for reducing reliance on chemicals used for sanitary and quarantine requirements. This paper deals with biological actions of ionizing radiation and its potential applications in the agri-food industry from the international point of view.

• Proceedings of the Korean Society of Postharvest Science and Technology of Agricultural Products Conference
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• 1996.10a
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• pp.21-21
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• 1996