• Journal of the East Asian Society of Dietary Life
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• v.8 no.4
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• pp.412-421
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• 1998

Physicochemical and microbiological properties of red beans, soybeans, barleys, and corns irradiated by gamma-ray at 1.2 kGy, 10.1 kGy, or 30.5 kGy were investigated. Moisture content and crude lipid content of the irradiated cereals showed no significant difference from the nonirradiated group. TBA values of corns irradiated at 30.5 kGy increased. Gamma irradiation reduced the numbers of mesophilic and psychrotrophic bacteria in the cereals. Yeasts and molds were reduced below detection levels even at 1.2 kGy dose-irradiation. There was no significant difference in reducing sugars between the irradiated cereals and the nonirradiated ones except corns. Stachyose, raffinose, and sucrose of soy beans and sucrose of barleys increased by 30.5 kGy dose-irradiation. Loss of riboflavin content of the irradiated samples was not observed except red beans irradiated at 30.5 kGy. In Hunter's color, b value of the red bean powder increased but L value of the soybean powder decreased by the Irradiation. L, a, and b values of the barley powder slightly increased under 30.5 kGy dose-irradiation and b value of the corn powder decreased under 10.1 or 30.5 kGy-dose irradiation.

• Korean Journal of Food Science and Technology
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• v.27 no.1
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• pp.30-35
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• 1995

Gamma irradiation was applied to non-glutinous and glutinous corns for improving starch isolation process. No significant changes in proximate composition of corn grains were observed by gamma irradiation. Irradiation at 1 and 5 kGy was effective for sterilizing all contaminated microorganisms of non-glutinous and glutinous corns, respectively. The moisture-uptake rate constants were increased in proportional to the steeping temperature and applied irradiation dose level. The irradiation efficacy on water absorption properties was also recognized in the corns stored for six months at room temperature. The combined use of gamma irradiation with sulfur dioxide solution was very effective for reducing steeping time. The starch yield gradually increased as irradiation dose levels increased. At 2 kGy, the sarch yield of non-glutinous and glutinous corns increased by 38% and 27%, respectively. No significant difference in Hunter's color value was observed between the starches isolated from nonirradiated and irradiated corn grains.

• Journal of the Korean Society of Food Science and Nutrition
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• v.32 no.1
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• pp.137-142
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• 2003

This study was carried out to examine the effects of gamma irradiation on the color removal, antioxidation, DPPH radical scavenger, and antimicrobial activity of Schizandra fructus extracts by different solvents. Schizandra fructus was extracted by hot water, ethanol, acetone and methanol, and the extracts were irradiated 10, 20 and 30 kGy with gamma rays. Hunter color L-value was increased by irradiation in a dose-dependent manner, resulting in brighter color for all solvents used. The a and b values were decreased by irradiation in a dose-dependent manner. Antioxidant activity of the ethanol extract of Schizandra fructus against soybean oil was the highest. The free radical scavenging activity was the strongest in hot water extract. All solvent extracts from Schizandra fructus had the strongest antimicrobial activities to B. subtilis, B. natto, B megaterium, S. aureus, Sal. typhymurium and E. coli. These results suggested that Schizandra fructus extracts have a strong potential as natural food preservatives and cosmetic raw materials. Furthermore, irradiation may not influence adversely on biological activites of the extracts when irradiated up to 30 kGy.

• Journal of the Korean Society of Food Science and Nutrition
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• v.32 no.2
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• pp.311-314
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• 2003

As a research on the practical approaches of gamma irradiation for the reduction of egg allergy, cakes including gamma-irradiated egg white were manufactured, and rheological characteristics and sensory qualities of the cakes were evaluated. Egg white was separated from whole egg and then gamma-irradiated with the absorbed dose of 10 or 20 kGy White layer cake, pound cake and sponge cake were made with irradiated egg white and used to the subsequent experiments. Firmness of all samples containing irradiated egg white was higher than that of control. Retrogradation of pound and sponge cakes containing irradiated egg white was delayed, and the result showed that the usage of irradiated egg white was better at the point of rheological storage ability. Effects of irradiated egg white on the sensory quality were different depending onto the properties of each product. Radiation off-odor was observed in the a11 samples containing irradiated egg white. To maintain the sensory Qualify, adequate methods such as masking effects should be developed during manufacture.

• Food Science and Preservation
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• v.10 no.3
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• pp.381-387
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• 2003

‘Fuji’ apples were treated by gamma irradiation (0 - 3 kGy) or methyl bromide fumigation at commercial conditions (MeBr, 26 g/kg, 4 hr) for quarantine purposes at two different treatment timing after harvest and stored under air at 0$^{\circ}C$ for 4 months. Associated with the treatment timing of irradiation or fumigation, after 40 days of storage at 0$^{\circ}C$ following harvest was more adequate than immediately after harvest in keeping qualities of stored apples. However, more than 2 kGy irradiation and MeBr fumigation were detrimental to physiological and chemical qualities of the fruits. These results show that less than 1 kGy irradiation at the delayed timing has a possibility to be applied as a quarantine procedure without significant changes in the quality of apples.

• Korean Journal of Food Science and Technology
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• v.31 no.6
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• pp.1488-1494
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• 1999

Effect of ${\gamma}-irradiation$ on the SDS-PAGE pattern, secondary structure content, the solubility of commercial soy protein isolate (SPI) and whey protein concentrate (WPC) was investigated. The change in the subunit molecular weight of SPI and WPC irradiated in aqueous solution or dried state was studied using SDS-PAGE. The SDS-PAGE pattern of SPI irradiated in aqueous solution revealed the fragmentation and aggregation of the subunit protein. For WPC irradiated in aqueous solution. fragmentation of the subunit protein up to 10 kGy was observed. In contrast, ${\gamma}-irradiation$ of SPI and WPC in dried state did not cause any significant changes in the SDS-PAGE pattern. The change In the secondary structure of irradiated SPI and WPC solution was studied using circular dichroism. The aperiodic structure content of SPI and WPC solution increased at higher irradiation doses, which suggests that ${\gamma}-irradiation$ caused the disruption of the ordered structure of SPI and WPC solution. Gamma-irradiation also caused the change in solubility of SPI and WPC in dried state.

• Journal of the Korean Society of Radiology
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• v.13 no.5
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• pp.819-824
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• 2019

In this study, we proposed a method for identifying isotopes generated from high-energy proton $^{nat}Pb$(p,xn) nuclear reactions through the difference of gamma rays generated through nuclear reactions using different proton energies. The experiment was performed by using a high energy proton generated from a 100 MeV proton linear accelerator of the Korea Atomic Energy Research Institute. Gamma rays generated by various nuclides generated through proton nuclear reactions were measured using a gamma-ray spectroscopy system composed of HPGe detectors. Gamma-ray standard sources were used for accurate energy calibration and efficiency measurements of HPGe gamma-ray detectors. For the proposed method, 100 and 60 MeV proton energy beams were used for the same natural lead samples. This method was found to be very effective in identifying nuclides produced by comparing gamma rays generated from the same sample with each other. The results of this study are expected to be very effective in obtaining other proton nuclear reaction results in the future.

• 대한방사선방어학회:학술대회논문집
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• 2009.11a
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• pp.140-141
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• 2009

• 대한방사선방어학회:학술대회논문집
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• 2009.11a
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• pp.152-153
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• 2009

• Proceedings of the Korean Institute of Information and Commucation Sciences Conference
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• 2017.10a
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• pp.702-704
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• 2017

In case of dismantling of nuclear power generation facility or radiation accident, the accurate information of gammaray source is essential for rapid decontamination. In order to more efficiently represent the position of the gamma ray to be removed, we create a spatial domain based on the real image. And we can perform decontamination of gamma-ray source more quickly by expressing the distribution of radiation source. The developed gamma ray imaging device overlaps with the visible image after gamma - ray detection and provides only two - dimensional image, but it does not show the distance information to the source. In this paper, we have developed a operation environment using the 3D visualization model for reporting effective decontamination operation.