• Korean Journal of Food Science and Technology
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• v.30 no.5
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• pp.1179-1183
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• 1998

Effects of gamma irradiation on beef spoilage were investigated by determination of the peroxide value, TBA value and total volatile basic nitrogen for 10 days at $4^{\circ}C$ or $25^{\circ}C$ after gamma irradiation up to 5 kGy in air or vacuum package. The total lipid contents were $4.4{\sim}4.7%$ and were not significantly changed by gamma irradiation up to 5 kGy. The peroxide value and thiobarbituric acid value increased with the elapse of the storage period. The level of lipid oxidation was higher at $25^{\circ}C$ than at $4^{\circ}C$ and higher in air package than in vacuum package and increased depending on the incremental irradiation doses level. Volatile basic nitrogen showed a lower content in the vacuum packaged samples irradiated at $3{\sim}5\;kGy$ than in non-irradiated samples over the storage period.

• Food Science of Animal Resources
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• v.28 no.5
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• pp.574-579
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• 2008

To develop a yogurt for sensitive consumer such as infants, children or immuno-compromised patients using gamma irradiation, the effects of gamma irradiation on the microbiological, chemical, and sensory quality in a commercial plain yogurt were investigated. No viable coliform bacteria were detected in the sample and approximately a 6 decimal reduction was achieved in the number of total aerobic bacteria by irradiation at 5 kGy. The initial population of lactic acid bacteria observed in the commercial plain yogurt was 8.95 log CFU/g. Gamma irradiation significantly reduced the initial microbial level to 6.47 and 2.85 log CFU/g after irradiation at 1 and 3 kGy, respectively (p<0.05). However, irradiation dose up to 5 kGy could not completely eliminate the lactic acid bacteria in commercial plain yogurt. pH, color, lactose and lactic acid content, and sensory quality were not affected by irradiation treatment and storage. Our results suggest that irradiation can improve the microbial quality of commercial plain yogurt without impairing the physicochemical and sensory quality.

• Fibers and Polymers
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• v.5 no.2
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• pp.156-159
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• 2004

Novoloid fibers have high chemical, flame and thermal resistance; however they have low tensile properties. Effects of gamma irradiation on the tensile properties of novoloid fibers have been investigated. Loop and knot resistance have also been examined. Maximum tenacity of the single fiber increased with an increase of the radiation dose applied. According to the loop and knot tenacity results it is found that brittleness has been also affected by the amount of radiation dose.

• Journal of Photoscience
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• v.9 no.1
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• pp.5-7
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• 2002

Direct irradiation of carbonyl compounds such as some aldehydes, ketones and anthraquinone in N,N-dimethylamiline(DMA), without using other solvents, gave $\beta$-hydroxyamines as the major products. Irradiation of anthrone and DMA in methanol afforded ${\gamma}$-hydroxyamine. The structure of the photoproduct was confirmed by treatment with an acid to give a bicyclic compound.

• Proceedings of the PSK Conference
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• 2003.10b
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• pp.139.1-139.1
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• 2003

Since radiotherapy has been suspected to promote tumor metastasis and the presence of increase levels of adhesion molecules have implications for metastasis, we decided to investigate whether gamma-irradiation alters the expression of intercellular adhesion molecule-1 (ICAM-1) on neuroblastoma cells and the activities of relevant intracellular signaling molecules. In the present study, the relative of ICAM-1 expression under gamma-irradiated neuroblastoma cells were assessed by Western blot analysis. (omitted)

• Korean Journal of Food Science and Technology
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• v.31 no.4
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• pp.1050-1056
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• 1999

The effect of ${\gamma}-irradiation$ was investigated on salted and fermented squid, squid jeotkal. Squid jeotkal was prepared with salt concentrations of 5%, 10% and 20% and was fermented at $15^{\circ}C$ and $25^{\circ}C$ after ${\gamma}-irradiation$ with doses of 0, 2.5, 5 and 10 kGy, respectively. Proximate composition, salinity, water activity (Aw), pH, total bacteria and sensory evaluation were examined during fermentation periods. Results showed that ${\gamma}-irradiation$ had no effect on proximate composition, salinity and Aw compared with non-irradiated squid jeotkal. However, pH and total bacteria, as well as sensory evaluation, were changed variously with processing conditions such as NaCl concentration, irradiation dose and fermentation temperature. The results of total bacteria and sensory evaluation showed that squid jeotkal with NaCl concentration of 10% and an irradiation dose of 10 kGy maintained high quality for 30 days at $15^{\circ}C$. Therefore, it was considered that ${\gamma}-irradiation$ was effective in processing low-salted squid jeotkal and extending its shelf-life without adding any food additives.

• Food Science and Preservation
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• v.15 no.3
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• pp.377-384
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• 2008

The gamma irradiation process was performed to prolong a shelf-life of peaches and the effects of a gamma irradiation on the nutritional, physiochemical and sensory characteristics of peaches were evaluated during a post-irradiation storage at $4^{\circ}C$ and $25^{\circ}C$. Nutritional, physiochemical and sensory characteristics of peaches were stable at 1 kGy of an irradiation, a recommended dose for fruits and vegetables by CODEX, and the viable cell counts of contaminated microorganisms were reduced by 2 decimal reduction, at this dose. After a 1-week storage at ambient condition, the microbiological quality of the 1 kGy irradiated peach was stable, while all the non-irradiated peaches were deteriorated Furthermore, cold storage enhanced the shelf-life of the gamma irradiated peach and the nutritional and physiochemical characteristics of the peaches were comparatively stable up to 6 weeks. Right after gamma irradiation, the sensory evaluation results were not different in any of the samples, and the sensory quality of the irradiated peaches was adequate for a 4-week storage at $4^{\circ}C$. Our results suggested that gamma irradiation at 1 kGy can be used to enhance the shelf-life of peach without a significant loss in the quality attributes, especially upon cold storage after radiation treatment.

• Journal of Mushroom
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• v.21 no.4
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• pp.247-253
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• 2023

In this study, we examined the effects of gamma irradiation dosage on the mycelial growth of Auricularia auricula-judae and performed analyses of fruiting body yield, growth characteristics, taste, fragrance, and mineral composition. Assessments of mycelial growth in response to gamma irradiation at different intensities revealed an enhancement in the growth of fungi exposed to irradiation at 200 Gy. Fruiting body yield was also highest at 200 Gy, followed by 800 Gy and the control group. On the basis of these observations, we subsequently applied gamma ray doses of 200 and 800 Gy to examine the effects of irradiation on fungal quality characteristics. In terms of the taste of fruiting bodies, we detected no significant differences among the control, 200 Gy, and 800 Gy groups. Contrastingly, with respect to fragrance, we found that fungi treated with 200 Gy were characterized by a pattern that differed from those of the control and other treatment groups. Furthermore, whereas we detected no significant difference among treatments with respect total dietary fiber content, calcium content was found to be higher in the treatment groups compared with the control group, with the highest content being measured in fungi exposed to 800 Gy irradiation. Copper content was confirmed to be higher in the control group, whereas there were no significant differences between the fungi irradiated with 200 and 800 Gy. Contrastingly, the highest levels of zinc were detected in response to 200 Gy irradiation, followed by 800 Gy. Collectively, our findings thus indicate that gamma irradiation can contribute to promoting increases in the fruiting body yield and mineral contents of mushrooms.

• Applied Biological Chemistry
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• v.51 no.2
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• pp.148-152
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• 2008

This study was to elucidate the effect of low dose gamma (${\gamma}$)-ray irradiation on the germination, seedling growth and antioxidant activity in sunflower seeds. The seed germination was stimulated in the range of 2.7${\sim}$8.0% by low dose ${\gamma}$-ray irradiation compared with that of the control; however, the germination of seeds stored for 4 months after irradiated was decreased at all low dose ${\gamma}$-ray irradiation groups. Especially, the germination rate of 32 Gy-irradiated seed group was much lower than that of the other groups and 8 Gy was the optimal radiation dose for germination at room temperature. Though there was variation with storage time and temperature, seedling growth stored at 10$^{\circ}C$ for 4 months after irradiated was promoted at the 1 Gy ${\gamma}$-ray irradiation group compared to seed stored at 25$^{\circ}C$. For the antioxidant activity of ${\gamma}$-ray irradiated seeds extract, 4 Gy and 32 Gy groups were significantly increased by 68.83% and 95.44%, respectively, compared to control at the concentration of 100 ${\mu}g$/ml.

• Korean Journal of Veterinary Research
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• v.41 no.3
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• pp.387-393
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• 2001

The chemical composition of fish feeds(mackerel, gizzard shad, shrimp and formula feed) were analyzed and compared with those of untreated and irradiated (5 kGy) feeds, and the effects of gamma irradiation (5 kGy) and butylated hydroxyanisole (BHA, 200ppm) on feeds spoilage were investigated by determination of thiobarbituric acid (TBA) value and peroxide value for 14 days at $20^{\circ}C$, $4^{\circ}C$ or $-20^{\circ}C$. Crude protein, crude lipid, crude fiber, crude ash and nitrogen free extract were not significantly changed by gamma irradiation with the dose of 5 kGy. Immediately gamma irradiation increased the initiative oxidation of feeds as expected. But BHA was found to be greatly effective in minimizing the radiation-induced peroxidation (p<0.05). The TBA value and peroxide value increased with the elapse of the storage period. The level of lipid oxidation was increased depending on the rise in storage temperature. But the additions of BHA inhibited the lipid oxidation (p<0.05).