• KSBB Journal
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• v.27 no.4
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• pp.222-226
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• 2012

In this study, the effect of gamma irradiation on the microbial contamination and biological activities of tuna cooking juices was investigated. Tuna cooking juice was by-produced during the canning processing, and had various functional components. But, it was shown that the tuna cooking juice was seriously contaminated. Gamma irradiation effectively reduced the microbial population in tuna cooking juice. Also, 1,1-diphenyl-2-picryl-hydrazyl (DPPH) radical scavenging activity, tyrosinse inhibitory activity, and ACE inhibitory activity of tuna cooking juices were all increased as a result of gamma irradiation. These results suggest that wasted tuna cooking juices can be used as a functional component in the food and cosmetic industries if the irradiation technology were applied.

• The Korea Journal of Herbology
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• v.24 no.1
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• pp.1-7
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• 2009

Objectives : The purpose of this study is to investigate on storage characteristics of Herbal materials treated with Gamma-irradiation(10 KGy). Methods : This experiments were carried out by field survey and storage characteristics were carried out by physicochemical determination. Results : Antimicrobial activity of oriental medicine materials(Angelica dahurica Radix, Glehnia littoralis Radix) were examined, together with investigation of effects on gamma-irradiation. Oriental medicine materials contaminated in microbial cell were tend to be pinhole in packaging materials(polypropylene) by bug and Larva. At the same time, PVDC (polyvinylldichloride) package also was founded in bug and Larva by microbial contamination during storage in room temperature. Conclusions : In conclusion, it is very desirable to dose gamma-irradiation(10 KGy) in these oriental medicine materials in order to prevent microbial activity.

• Journal of the East Asian Society of Dietary Life
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• v.8 no.4
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• pp.430-440
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• 1998

Meat is a perishable product since it offers favorable conditions for microbial contamination and multiplication. Besides, undercooked and raw meat has been linked to outbreaks of hemorrhagic diarrhea due to the presence of microbial pathogens. Therefore, this study was conducted to find out the effect of the use of gamma-irradiation in order to improve preservation and eliminate this microorganisms. The Initial level of microbial contamination in pork was 1.1$\times$10$^3$ CFU/g (aerobic bacteria), 5.3$\times$10$^3$CFU/g (psychrophile), 3.1$\times$10$^3$ CFU/g (coliforms) and 3.2$\times$10$^3$ CFU/g(Listeria), All kinds of contaminated microorgnisms were sterilized by gamma irradiation at 3 kGy. The proximate composition of pork was not significantly changed by irradiation dose and storage period. The pH was slightly increased during storage period and titratable acidity decreased. However, no significant changes in pH and acidity were observed by gamma irradiation. There was no difference in total amino acid content regardless of irradiation dose and storage period. Glutamic acid was detected at high levels throughout the storage period. The major mineral compositions of pork were potassium, phosphorus, sodium, magnesium. No significant difference in the components of minerals were observed by gamma irradiation.

• Preventive Nutrition and Food Science
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• v.9 no.3
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• pp.236-239
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• 2004

Microbial contamination of ready-to-eat ingredients for Kimbab manufacturing and the effect of irradiation to reduce the microbial contamination of the products were investigated. Among 9 food items tested, there were no viable cells in the ham, seasoned and cooked beef, imitation crab leg, fried egg, and seasoned burdoc. Cucumber, surimi gel, and seasoned and blanched spinach were counted at 5.07$\pm$0.97, 3.50$\pm$0.14, and 5.41$\pm$0.51 log CFU/g, respectively. Irradiation at 1 kGy reduced the number of microorganism in these ready-to-eat foods to an undetectable level. However, the dried laver showed an 8.83$\pm$0.10 log CFU/g and an irradiation at 3 kGy reduced the level to only 7.14$\pm$0.23. Sensory evaluation of the irradiated Kimbab prepared from these food materials indicated that the measure of the control of the sensorial quality should be provided before applying an irradiation to the prepared Kimbab.

• Korean Journal of Pharmacognosy
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• v.36 no.3 s.142
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• pp.220-223
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• 2005

The purposes of this study was to develop the best one among the methods using dry heat, gamma irradiation and alcohol gas, to sterilize Scutellariae Radix selected based on high frequency of circulation between merchants and high susceptibility to microbial contamination, through comparing these methods in terms of the followings; ⅰ) the efficacy of sterilization in comparison with cost, and ⅱ)the alteration of chemical components of these herbal medicines. The results of this study will be taken advantage of establishment of the maximum limit of microorganism contaminated in herbal medicines. From the results of this study we conclude the followings: ⅰ) The sterilizing method using dry heat may be inappropriate, because it seriously changed their color and morphology which is an essential criterion to estimate a measure of quality between merchants and consumers, although it effectively got rid of contaminated microorganism and did not alter major components, baicalin; ⅱ) The sterilizing method using gamma irradiation may be appropriate, because it showed a strong sterilizing effect, and no alteration of chemical components, color and morphology; ⅲ)The sterilizing method using alcohol gas may also be appropriate, because it had a similar effects as in the case of gamma irradiation. Collectively, we suggest that appropriate sterilizing methods to guarantee the microbial quality of this herbal medicine may be those using gamma irradiation and alcohol gas.

• YAKHAK HOEJI
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• v.50 no.6
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• pp.415-420
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• 2006

The purpose of this study was to develop the best methods to sterilize herbal medicines which is frequently used and known to have high susceptibility to microbial contamination. We used dry heat, gamma irradiation and alcohol gas treatment for sterilization, and evaluated these methods in terms of the followings; i) the efficacy of sterilization, and ii) the chemical alteration of index constituents of herbal medicines. Treatment with dry heat effectively eliminated the contaminated microorganisms, and did not significantly alter the content of berberine chloride, paeoniflorin and amygdalin in Phellodendron Bark, Peony Root and Apricot Kernel, respectively: However it seriously changed the color and morphology which are essential criteria to estimate a measure of quality of herbal medicines. Treatment with gamma irradiation showed a strong sterilizing effect, and no alteration of the content of index constituents, color and morphology: Alcohol gas treatment resulted in similar effects as those in gamma irradiation. Collectively; these results suggest that treatment with gamma irradiation or alcohol gas may be useful methods for sterilizing herbal medicines without a decrease in their microbial quality.

• Journal of the Korean Society of Food Science and Nutrition
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• v.32 no.7
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• pp.991-996
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• 2003

Determination of regional microbial contamination in the process of rice rolled in dried laver (Kimbab) and effects of gamma irradiation on the improvement of hygienic quality and shelf stability were investigated. Total aerobic bacterial distribution of raw materials of Kimbab were; 10$^{6}$ ∼10$^{7}$ CFU/g in dried laver, 10$^3$ CFU/g in cucumber and below 10 CFU/g in steamed rice, ham, fried egg, and salted radish. Total coliform bacteria were 10$^3$ CFU/g in dried laver and detected below detection limit (10 CFU/g) in other raw materials. And it was arithmetically calculated that the levels of total aerobic bacteria and coliform bacteria in Kimbab does not exceed 10$^{5}$ CFU/g and 10$^1$ CFU/g under the aseptic process, respectively. However, microbial contamination levels in just prepared Kimbab in a market were about 10$^{6}$ CFU/g of total aerobic and coliform bacteria. Therefore, it was considered that microbial contamination of Kimbab is mainly originated from environmental uptake during the preparation. The representative media for putrefying bacterial growth were steamed rice. Coliform bacteria were mainly increased in ham and fried egg during storage. The bacteria in dried laver were radio-resistant and survived at 3 kGy of gamma irradiation. Coliform bacteria on EMB agar plate were eliminated at the dose of 2 kGy. The sensory acceptability of 2 kGy irradiated Kimbab was stable and the Kimbab can be preserved for 24 hour at 15$^{\circ}C$. Therefore, it was considered that optimal irradiation dose for radicidation of Kimbab was 2 kGy.

• Journal of Radiation Industry
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• v.4 no.4
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• pp.381-384
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• 2010

In this study, the microbial safety and mechanical properties of xeno-bone graft material irradiated were investigated during the storage. Xeno-bone graft of the deminerlized bone matrix in carboxy-methyl-cellulose was gamma-irradiated and was cultured in PCA and PDA agar to check microbial contamination. Total aerobic bacteria and fungi were not detected in the irradiated and non-irradiated sample stored in accelerator at $30^{\circ}C$ for 10 months. Viscosity of CMC treated gamma irradiation was also not changed by holding period.

• Food Science and Preservation
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• v.30 no.5
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• pp.729-742
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• 2023

The consumption of king oyster mushrooms has steadily increased owing to their unique flavor and delicate texture. This study extended the storage period of king oyster mushrooms (Pleurotus eryngii ) via gamma irradiation. Irradiated samples (0, 0.5, 1, 2, and 3 kGy) were stored at 4℃ with 80% relative humidity for up to 28 days, and the experiments were conducted every 7 day. Microbiological analysis revealed a dose-dependent reduction in total aerobic bacteria, Pseudomonas spp., and yeasts and molds, and gamma irradiation above 2 kGy effectively controlled microbial contamination for up to 28 days. At the 28th day of storage, the irradiated king oyster mushrooms exhibited delayed browning through the reduction of tyrosinase activity. Moreover, firmness reduction (%) was 80.59±1.89% for the non-irradiated group and 42.80±1.28, 34.57±1.13, 31.05±3.24, and 39.73±0.94% for the irradiated group (0.5, 1, 2, and 3 kGy), respectively. These results were supported by the scanning electron microscopy photos, which showed smaller pores in the irradiated group than in the non-irradiated group. This study demonstrated that 2 kGy of gamma irradiation effectively reduces microbial contamination and delays the browning and softening of king oyster mushrooms for up to 28 days.

• Culinary science and hospitality research
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• v.8 no.3
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• pp.249-257
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• 2002

Gamma irradiation(1~10 kGy) was applied to chicken for the evaluation of their microbiological safety. In 3kGy-irradiated sample, the initial level of microbial contamination in chicken was 1.8$\times$10$^4$CFU/g (Coliforms), 2.2$\times$10$^3$CFU/g(Salmonella) and 2.7$\times$10$^3$CFU/g(Listeria), All kinds of contaminated microorganism were sterilized by 7kGy-irradiation. Also, irradiation followed by freeze storage at the same time was very effective in inhibiting bacterial growth. The pH was slightly increased during storage period and titratable acidity decreased. However, no significant changes in pH and acidity were observed by gamma irradiation.