• Title/Summary/Keyword: 전자선 조사

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Effect of Gamma Irradiation on Microbial Growth, Electron Donating Ability, and Lipid Oxidation of Marinated Beef Rib (Galbi) with Different Packaging Methods (포장방법에 따른 양념갈비의 저장 중 총균수, 전자공여능 및 지방산화의 감마선 조사효과)

  • 강호진;조철훈;이나영;김정옥;변명우
    • Journal of the Korean Society of Food Science and Nutrition
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    • v.33 no.5
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    • pp.888-893
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    • 2004
  • The effect of irradiation and packaging methods (vacuum vs aerobic) on microbial growth, electron donating ability, and lipid oxidation in marinated beef rib (Galbi) was investigated. The total aerobic bacteria in Gazlbi reduced significantly with the increase of irradiation dose, and the effect was more significant in the Galbi with vacuum packaging, The pH showed a decreasing trend during storage and this change was more significant in the Galbi with aerobic packaging. Electron donating ability of Galbi was reduced by irradiation in aerobic packaging but no difference was found in vacuum packaging except 7 days. The 2-thiobarbituric acid reactive substances (TBARS) value of Galbi increased by irradiation in aerobic packaging during storage time, but that of vacuum packaging was maintained an initial value. Results indicated that irradiation coupled with vacuum packaging may enhance the microbial safety of Korean traditional meat products, Galbi, with minimum quality changes during storage.

Evaluation of Electron Beam Dose Distribution by Age Diffusion Equation (연령 확산 이론에 의한 전자선의 조직내 선량분포 평가)

  • 추성실
    • Progress in Medical Physics
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    • v.4 no.1
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    • pp.29-39
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    • 1993
  • Electron beams have found unique and complementary used in the treatment of cancer, but it's very difficult to delineate dose distribution, because of multi-collisions. Numerical solution is more usefull to describe electron distributed in tissue. A semi-empirical eqution is given for the dose at any point at various depths in water. This equation is a modificated model which was based on solutions of a general age diffusion equation. Parameters have been calulated from electron beams data with energies 6~18MeV form a LINAC for use in computerised dosimetry calculations. The depth doses and isodose curves are predicted as a function of the practical range, source skin distance and field size. Depth dose accuracy have been achieved 2% above 50% depth dose and 5% at lower doses, relative to maximum dose. Also, the shape of the isodose curves with the constrictions at higher dose and bulging ot lower values are accurately predicted. Computer calculated beams have been used to generate ever isodose distribution for certain clinical situations.

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Effects of Starter Cultures on the Quality Traits of Electron Beam Irradiated Fermented Meat during Aging (전자선 조사된 원료육과 Stater Culture의 사용이 발효육의 숙성 중 품질에 미치는 영향)

  • Lim, Dong-Gyun;Seol, Kuk-Hwan;Lee, Moo-Ha
    • the MEAT Journal
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    • s.35 winter
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    • pp.46-55
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    • 2008
  • The microbiological and physicochemical properties of irradiated (2 kGy) or non-irradiated fermented meats processed with or without a commercial starter culture were evaluated during fermentation and aging. The pH of irradiated (2 kGy) fermented meats with starter cultures dramatically decreased during fermentation and aging (p<0.05), and the final pH was 4.25. The total aerobic counts and lactic acid bacteria counts reflected the addition of the starter culture. As the fermentation progressed, the total aerobic counts closely paralleled the lactic acid bacteria counts. The TBARS values of irradiated fermented meats increased regardless of the treatment during fermentation and aging. These results show that the irradiated(electron-beam) meat/fat resulted in the reduction of the total microbes and survives lactic acid bacteria. The use of starter cultures in meat batters post-irradiation may be useful for the production of fermented meats.

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Effects of Starter Cultures on the Quality Traits of Electron Beam Irradiated Fermented Meat during Aging (전자선 조사된 원료육과 Stater Culture의 사용이 발효육의 숙성 중 품질에 미치는 영향)

  • Lim, Dong-Gyun;Seol, Kuk-Hwan;Lee, Moo-Ha
    • Food Science of Animal Resources
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    • v.27 no.3
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    • pp.308-313
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    • 2007
  • The microbiological and physicochemical properties of irradiated (2 kGy) or non-irradiated fermented meats processed with or without a commercial starter culture were evaluated during fermentation and aging. The pH of irradiated (2 kGy) fermented meats with starter cultures dramatically decreased during fermentation and aging (p<0.05), and the final pH was 4.25. The total aerobic counts and lactic acid bacteria counts reflected the addition of the starter culture. As the fermentation progressed, the total aerobic counts closely paralleled the lactic acid bacteria counts. The TBARS values of irradiated fermented meats increased regardless of the treatment during fermentation and aging. These results show that the irradiated (electron-beam) meat/fat resulted in the reduction of the total microbes and survives lactic acid bacteria. The use of starter cultures in meat batters post-irradiation may be useful for the production of fermented meats.

Research of 6 MeV Electron Dose Distribution (6 MeV Electron Therapy에서의 Electron Dose Distribution에 관한 연구)

  • Je Jae-Yong;Park Chul-Woo;Jin Sung-Jin;Park Eun-Tae
    • The Journal of Korean Society for Radiation Therapy
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    • v.17 no.2
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    • pp.161-166
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    • 2005
  • Purpose : Electron is used for the treatment of skin cancer, breast cancer, and head and neck cancer in clinic. Our study is performed to check the isodose distribution in source surface distance(SSD)and source bolus distance(SBD)setup, nipple influence to isodose distribution of electron, junctional area isodose variation of photon and electron field. Materials and Methods : The electron dose distribution measures the diameter for 20 cm hemisphere paraffin phantom 2 made. It inserted the film between 2 paraffin phantom and it investigated it got radiation and dose distribution curve. Results : The 8% of isodose difference is with the surface distance(SSD)and source bolus distance(SBD)setup. The electon when the nipple exists inside the field, as nipple size it cuts the bolus and when it puts out and there is a possibility of getting the dose distribution which is homogeneous. When in the junction of electron and photon it uses the bolus it uses in the electron field whole, there is a possibility of getting the dose distribution which is homogeneous. Conclusion : The dose distribution decrease from the SBD setup. To reduce the influence of nipple, corresponding volume of bolus should be removed. And bolus covering all the electron field reduced hot and cold spot of junctional area of photon. In the future becomes the research which sees an effective electron therapy.

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The Defect Characterization of $Gd_2O_2S$: Tb Crystals by Positron Annihilation Spectroscopy (양전자 소멸 분광법을 이용한 $Gd_2O_2S$ : Tb 결함 특성)

  • 이종용;김창규
    • Journal of the Korean Vacuum Society
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    • v.13 no.2
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    • pp.92-98
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    • 2004
  • DBPAS has been used to characterize atomic size defect structures in materials. In this investigation the numerical analysis of the Doppler spectra was employed to the determination of the shape parameter, S, defined as the ratio between the amount of counts in a central portion of the spectrum and the total counts of whole spectrum. As the samples were exposed by X-ray increasing the exposed doses from 3, 6, and 9 Gy with 6 MV and 15 MV, respectively and also irradiated by X-ray as the medical applications used for in 0, 2, 4 and 6 years. The S-parameter values were increased as increasing the exposed time and the energies, that indicated the defects generate more. The S-parameters of the samples with medical treatment is varied from 0.4932 to 0.4956.

Investigation on the Increase of Antioxidant Activity of Cooking Drip from Enteroctopus dofleini by Irradiation (방사선 조사에 의한 문어 자숙액의 항산화 활성 증가 원인 규명)

  • Choi, Jong-Il;Kim, Yeon-Joo;Sung, Nak-Yun;Kim, Jae-Hun;Ahn, Dong-Huyn;Chun, Byung-Soo;Cho, Kook-Yeon;Byun, Myung-Woo;Lee, Ju-Woon
    • Journal of the Korean Society of Food Science and Nutrition
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    • v.38 no.1
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    • pp.121-124
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    • 2009
  • This study was conducted to investigate the reason for the increase in the antioxidant activity of cooking drip from Enteroctopus dofleini by gamma and electron-beam irradiation. To define the effect of irradiation on the antioxidant activity of polyphenol in cooking drip, polyphenol excluded cooking drip extracts were prepared with polyclar$^{TM}$. But, the antioxidant activity of the cooking drip extracts without polyphenol was still increased by both irradiations. Instead, the effect on the proteins in the cooking drips prepared by ammonium sulfate precipitation showed great increase in antioxidative activity by irradiation. From these results, it was concluded that the increase in the antioxidative activity in cooking drips by the irradiation was caused by the structural modification of proteins in the cooking drips.

Effects of Electron-Beam Irradiation on Saponins and Physio-chemical Properties of Ginseng Powders (Electron Beam 조사가 인삼분말의 사포닌 및 생리화학적 특성에 미치는 영향)

  • 이미경;이종원;도재호;권중호
    • Food Science and Preservation
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    • v.10 no.2
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    • pp.206-212
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    • 2003
  • Comparative effects of electron beam and gamma-ray irradiation (25 ∼15 kGy) were investigated on saponin stability and some physiological and chemical properties of white and red ginseng powders. Saponin components were found stable upon irradiation of both energies when determined by TLC and HPLC, after 4 months of storage at room temperature as well as immediately after treatment The contents of total phenolics and acidic polysaccharides of the samples were higher in red ginseng than in white. Polysaccharide contents increased with irradiation doses. Amylase activity of white ginseng was stimulated by irradiation but decreased with the lapse of storage time. There were no apparent differences in electrophoresis patterns of extracted proteins depending on irradiation doses and energy sources.

Structural Changes of Homopolymer Polypropylene Foam with Molecular Weights and Rheological Properties : (1) In Batch Process (분자량 및 유변 특성에 따른 단일 중합체 폴리프로필렌의 발포체 변화 : (1) 회분식 공정)

  • 홍다윗;윤광중;이기윤
    • Polymer(Korea)
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    • v.26 no.1
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    • pp.61-70
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    • 2002
  • The effects of molecular weights and rheological properties of polypropylene (PP), on its foam structures in batch process were investigated. The effects of crosslinking process were also considered in this study. The rheological properties of polypropylene, such as storage modulus(G'), loss modulus(G"), zero shear viscosity($\eta_O$), and relaxation time($\lambda$), increased with the increase of molecular weights, and these increases in rheological properties directly affected the stability improvements of the PP foam. The increase of crosslinked PP's gel content stopped at the irradiation dose of 3.2 Mrad. The development of foam structures was more enhanced as the irradiation dose increased up to 3.2 Mrad. When the irradiation dose exceeded 3.2 Mrad, however, it negatively affected the structural development of the foam by diminishing gel contents of the foaming material, which resulted in instability of the foam structure.ture.