• Korean Journal of Food Science and Technology
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• v.14 no.2
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• pp.136-140
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• 1982

In order to evaluate the feasibility for the sterilization of Korean red and white ginseng powder by irradiation, red and white ginseng powder (120 mesh) was irradiated by 0.1, 0.3, 0.5, 0.7, 1.0 and 2.0 Mrad with $^{60}Co$ irradiator (dose rate: 4000 rad/h). Extraction rate of crude saponins by buthanol and by 50% ethanol were slightly increased according to the irradiation dose (buthanol ex. 1.7%, 50% ethanol ex. 2.6% at 1.0 Mrad irradiation. There are no remarkable changes in HPLC patterns of crude saponins by radiation. It was found that irradiation up to 1 Mrad on Korean ginseng products have no significant effect on proximate component, reducing sugar and amino nitrogen of ginseng powder and on the color density of ginseng extract with 50% ethanol. Irradiation up to 1 Mrad could be utilized for the sterilization of Korean ginseng powder whithout changes of physicochemical properties.

• Journal of Radiation Industry
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• v.8 no.2
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• pp.83-88
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• 2014

Application of X-ray irradiation of dried condiments was studied using commercially prepared dried garlic, onion and welsh onion flakes as model samples. Total load of aerobic microbes (TAM), color differences, and generation of off-flavor were quantified for samples individually irradiated with gamma rays, electrons, or X-rays. TAM load was decreased by irradiation in a dose-dependent manner. The three types of radiation did not differ in the extent of TAM reduction (P>0.05). The samples did not differ in color. Off-flavor was detected from 6 kGy-irradiated samples, regardless of radiation sources. The results indicated that X-ray irradiation could be used for irradiation of dried condiments with the same effects as gamma rays and an electron beam.

• Journal of Radiation Industry
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• v.8 no.1
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• pp.1-5
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• 2014

This study investigated the reduction of microbial population and sensory properties in red pepper powders irradiated by gamma ray, electron beam, and X-ray. Populations of total aerobic bacteria and yeast & molds in red pepper powders were decreased by irradiation treatment in a dose-dependent manner. Gamma ray, electron beam, and X-ray at doses above 8 kGy caused 100% inhibition on growth of aerobic bacteria in red pepper powders. Inhibitory activity of X-ray on sterilization of red pepper powders was significantly equal to or higher compared to gamma ray and electron beam. Color and off flavor in red pepper powders were no significant difference among the control and samples irradiated with gamma ray, electron beam, and X-ray. As a result, the gamma ray, electron beam, and X-ray irradiation can be used to sterilize the microbial growth in red pepper powders without quality loss.

• Journal of Food Hygiene and Safety
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• v.15 no.2
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• pp.114-121
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• 2000

A study was carried out to establish a detection method for irradiated black and white pepper. Samples were packed in polyethylene bags and irradiated with 2.5, 5, 7.5, 10 and 15 kGy using a Co-60 irradiator. The samples were suspended in water, and alkalized with sodium hydroxide solution. Apparent viscosity was determined after heat gelatinization using a Brookfield DV-III rotation viscometer at 30。C with 30, 60, 90, 120, 150, 180, and 210 rpm. Means and standard deviations of the viscosities of all samples decreased by increasing the stirring speeds. The viscosities increased in all samples by increasing the concentration. Regression expressions and coefficients of viscosity which decreased with increasing irradiation dose of 10% and 13% black pepper, and 7% and 10% white pepper were 0.9531 (y=-131.29x+1,769.0), 0.9725 (y=-351.33x+4,036.0), 0.9731 (y=2,208.0e${^-0.3546X}$), and 0.9959 (y=5,116.0e${^-0.2887X}$), respectively, at 120 rpm. This trend was similar fur all stirring speeds. These results suggest that the detection of irradiated black and white pepper at various doses is possible by the viscometric method.

• Journal of the Korean Society of Food Science and Nutrition
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• v.43 no.10
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• pp.1588-1593
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• 2014

This study evaluated the genotoxic effects of 30 kGy of X-ray irradiation to four foods (chicken, egg powder, dried green onion, and black pepper). In bacterial reversion assay with Salmonella Typhimurium TA98, TA100, TA1535, and TA1537, the X-ray irradiated foods did not show a significantly increased number of revertant colonies in the presence or absence of the S9 metabolic activation system. In chromosomal aberration tests with Chinese hamster ovary (CHO) cells, the X-ray irradiated foods showed no increase in the frequency of chromosomal aberrations. In in vivo mouse micronucleus assay, the X-ray irradiated foods did not show any increase in the frequency of polychromatic erythrocytes with micronuclei. These results indicate that 30 kGy of X-ray irradiation to four foods (chicken, egg powder, dried green onion, and black pepper) showed no genotoxic effects under these experimental conditions.

• Journal of Radiation Industry
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• v.7 no.2_3
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• pp.177-182
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• 2013

This study was conducted to evaluate the effect of gamma irradiation on the microbial populations of dried raw materials (9 products) and Saengsik powder. The samples were gammairradiated at doses of 2, 4, 6 and 8 kGy and the microbiological populations were evaluated. The total numbers of bacteria and Bacillus cereus in non-irradiated dried-raw materials for Saengsik powder was 1.3~3.4 and $1.7{\sim}2.4log\;CFU\;g^{-1}$. However, gamma irradiation reduced the microbiological populations in all samples, and Saengsik powder were sterilized at more than 6 kGy. Moreover, Clostridium perfringens were not observed in all samples within detection limit (<$1log\;CFU\;g^{-1}$). Therefore, the results of this study suggest that gamma irradiation at 6 kGy is sufficient to sterilize Saengsik powder, and thus, irradiated Saengsik powder at 6 kGy fulfills the microbiological requirements for sterilized food.

• Journal of Radiation Industry
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• v.7 no.2_3
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• pp.93-99
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• 2013

This study was conducted to evaluate the effect of gamma irradiation on the microbiological and sensory characteristics of frozen Bibimbap. Frozen Bibimbap vegetables were contaminated by microbial levels of $2.70{\sim}6.67log\;CFU\;g^{-1}$ in total aerobic bacteria. Frozen Bibimbap was contaminated by microbial levels of $4.8log\;CFU\;g^{-1}$ in total aerobic bacteria, but microorganisms in gamma-irradiated samples at above 25 kGy were not found at detection limit less then $1log\;CFUg^{-1}$. Sensory characteristics of the gamma-irradiated Bibimbap were decreased depending upon the irradiation dose, and sensory scores of the samples irradiated with doses higher than 10 kGy were significantly decreased. Therefore, the application of combination of the various food processing technology should be considered for the sterilization of Bibimbap, without any deterioration of quality occurred by high dose irradiation.

• Korean Journal of Food Science and Technology
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• v.31 no.6
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• pp.1495-1502
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• 1999

Gamma-irradiated beef and chicken at the dose levels of 0.5 to 10 kGy were subjected to the detection of radiation-induced 2-alkylcyclobutanones whether irradiated or not. Radiation-induced 2-alkylcyclobutanones were extracted from beef and chicken fats, separated by florisil column chromatography and identified with GC/MS method by selected ion monitoring(SIM). When beef and chicken were irradiated, 2-dodecylcyclobutanone, 2-tetradecylcyclobutanone and 2-(5'-tetradecenyl)cyclobutanone were formed from palmitic, stearic and oleic acids. Concentrations of 2-alkylcyclobutanones were linearly increased with the dose levels of irradiation and depended upon the composition of fatty acids in beef and chicken. Radiation-induced 2-alkylcyclobutanones in irradiated beef and chicken were remarkably detected at 1 kGy and over, while these compounds were not detected in non-irradiated samples. The concentrations of radiationinduced 2-alkylcyclobutanones were relatively constant during 6 months.

• Korean Journal of Food Science and Technology
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• v.45 no.2
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• pp.248-251
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• 2013

The purpose of this study was to investigate the inactivation effect of intense pulsed light (IPL) on Micrococcus roseus, an irradiation-resistant bacterium isolated from laver, and the commercial feasibility of this sterilization method on dried laver. The inactivation of M. roseus in cultivated plates increased with increasing light intensity and treatment time. Approximately 6.6 log CFU/mL reduction of the cell viability was achieved with IPL treatment for 3 min at 1,000 V of light intensity, tailing was not shown. In addition, the inactivation rate of M. roseus increased with increasing pulse number at same light intensity and treatment time. The killing efficiency for M. roseus increased with by decreasing the distance between the light source and the sample surface.

• Journal of Radiation Industry
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• v.5 no.2
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• pp.175-178
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• 2011

This study was conducted with effect of lactic acid bacteria by gamma irradiation. Lactic acid bacteria were exposed to irradiation with a single absorbed dose of 1, 2, 3, 4, 5, 6, 8, and 10 kGy. Possible lactic acid bacteria, including Lactobacillus paracasei KCTC 13169, Lactobacillus casei KCTC 3109, Lactobacillus acidophilus KCTC 3140, Lactobacillus plantarum subsp plantarum KCTC 3103, Lactobacillus debruekii subsp bulgaricus KCTC 3635, Streptococcus thermophilus KCTC 3658 were selected. The radiation sesitivities of lactic acid bacteria were expressed as $D_{10}$ values. The $D_{10}$ values of Lactobacillus paracasei, Lactobacillus casei, Streptococcus thermophilus, Lactobacillus acidophilus, Lactobacillus plantarum, and Lactobacillus debruekii were calculated as 0.42, 0.51, 0.47, 0.90, 0.44, and 0.61 kGy, respectively. Results suggest that L. acidiphilus has the highly resistant to gamma irradiation.