• 한국식품저장유통학회:학술대회논문집
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• 한국식품저장유통학회 1996년도 정기총회 및 제9차 학술발표회 진행표 및 발표논문 초록
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• pp.21-21
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• 1996

• Preventive Nutrition and Food Science
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• 제9권3호
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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.

• 한국식품영양과학회지
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• 제26권6호
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• pp.1116-1121
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• 1997

Effects of gamma irradiation onf the activity and the properties(amino acid compositions, in vitro digestibility and SDS-PAGE pattern) of proteolytic enzymes were investigated. The proteolytic activity of soluble human serine protease, enzyme in kiwi and pineapple decreased 10% and 30~65% by 5 kGy and 30 kGy, respectively. In dried pancreatin and lysozyme, the proteolytic and antimicrobial activities decreased 6~14% and 10~20% by 5kGy and 40kGy, respectively. The analysis of above 10kGy-irradiated soluble human serine protease by SDS-PAGE revealed radiolysis of the enzyme into protein or peptides of lower molecular weights. The irradiation of skim milk, hammastein casein, and lysozyme up to 40kGy had no deleterious effect on either the in vitro digestibility or amino acid compositions.

• Food Science and Biotechnology
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• 제17권4호
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• pp.861-864
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• 2008

Enterobacter sakazakii, Salmonella typhimurium. and Bacillus cereus were evaluated on inoculated infant formula by gamma irradiation treatment as a method to provide microbial safety. The infant formula inoculated with the major pathogenic bacteria was treated at irradiation dose of 0, 3, 5, and 10 kGy, respectively. After treatment, the samples were individually packaged and stored at $20^{\circ}C$. Microbiological data during storage represented that the populations of E. sakazakii, S. typhimurium, and B. cereus were reduced with the increase of irradiation dose by 4 to 5 log reductions. In particular, E. sakazakii, S. typhimurium. and B. cereus were eliminated at 10, 5, and 3 kGy, respectively. E. sakazakii was the most radiation-resistant, while B. cereus was the least. Our results represent that gamma irradiation below 10 kGy should eliminate the growth of the major pathogenic bacteria in infant formula during storage.

• Preventive Nutrition and Food Science
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• 제11권4호
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• pp.344-347
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• 2006

This study evaluated the use of electron beam irradiation for decontamination of the Korean medicinal herb, Angelica gigas Nakai. Herb samples were irradiated at doses of 2, 8, and 16 kGy, respectively. Populations of microorganisms in Angelica gigas Nakai decreased by 2$\sim$3 log cycles at 8 kGy irradiation. Electron beam irradiation caused negligible changes in Hunter color L, a, and b values. Sensory evaluations of Angelica gigas Nakai confirmed that irradiation caused no significant changes in the organoleptic properties of the samples. These results suggest that electron beam-irradiated herbs retain a better microbial safety and sensory qualities, compared with the non-irradiated.

• 한국식품과학회지
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• 제30권5호
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• pp.1184-1188
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• 1998

한우육의 사태(M.Semitendinosus)를 대상으로 방사선 조사선량(0, 1, 3, 5 kGy), 포장방법(함기, 진공) 및 저장기간에 따른 육색소(myoglobin, oxymyoglobin, metmyoglobin)와 Hunter값의 변화를 측정하였다. Hunter값의 경우 저장기간이 경과함에 따라 명도와 황색도는 증가하는 경향을 나타내었으나, 적색도는 감소하였고, 감마선 조사에 의한 영향으로는 명도, 황색도, 적색도값이 조사선량이 증가함에 따라 감소하였다. Myoglobin의 함량은 저장기간이 경과할수록 모든 시험군에서 감소를 나타내었고, oxymyoglobin과 metmyoglobin은 점차적으로 증가하였으며, 방사선 조사에 따른 영향은 조사선량이 증가함에 따라 myoglobin은 감소되고 oxymyoglobin과 metmyoglobin은 다소 증가하는 경향을 나타내었다. 포장방법에 따른 영향에서는 함기 포장군이 진공포장군에 비해 더 큰 육색소의 변화를 나타내었다.

• Journal of Microbiology and Biotechnology
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• 제33권1호
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• pp.106-113
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• 2023

The supply of microbiological risk-free water is essential to keep food safety and public hygiene. And removal, inactivation, and destruction of microorganisms in drinking water are key for ensuring safety in the food industry. Ultraviolet-C (UV-C) irradiation is an attractive method for efficient disinfection of water without generating toxicity and adversely affecting human health. In this study, the disinfection efficiencies of UV-C irradiation on Shigella flexneri (Gram negative) and Listeria monocytogenes (Gram positive) at various concentrations in drinking water were evaluated using a water purifier. Their morphological and physiological characteristics after UV-C irradiation were observed using fluorescence microscopy and flow cytometry combined with live/dead staining. UV-C irradiation (254 nm wavelength, irradiation dose: 40 mJ/cm²) at a water flow velocity of 3.4 L/min showed disinfection ability on both bacteria up to 10⁸ CFU/4 L. And flow cytometric analysis showed different physiological shift between S. flexneri and L. monocytogenes after UV-C irradiation, but no significant shift of morphology in both bacteria. In addition, each bacterium revealed different characteristics with time-course observation after UV-C irradiation: L. monocytogenes dramatically changed its physiological feature and seemed to reach maximum damage at 4 h and then recovered, whereas S. flexneri seemed to gradually die over time. This study revealed that UV-C irradiation of water purifiers is effective in disinfecting microbial contaminants in drinking water and provides basic information on bacterial features/responses after UV-C irradiation.

• 한국식품과학회지
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• 제31권4호
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• pp.1005-1010
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• 1999

감마선 조사가 쇠고기의 연도개선에 미치는 효과를 조사하기 위하여 도축 직후 쇠고기에 감마선을 조사시켜 전단력의 변화 및 근육의 미세구조를 관찰하였다. 감마선이 조사된 쇠고기는 최고 전단력치에 도달하는 시간이 감마선 조사선량이 증가함에 따라 단축되었다. 감마선 조사가 근육의 초미세구조에 작용하여 근절의 단축을 지연시켰고, Z-line의 수축을 유도하였다. 또한 감마선이 조사된 쇠고기에서 근속과 perimysium의 파괴는 감마선 비조사구에 비해 더 빨리 진행되는 것이 관찰되었다. 결론적으로 감마선 조사는 쇠고기의 사후경직에 도달하는 시간을 단축시키고, 연도개선 효과에 유효한 것으로 사료된다.

• 한국식품위생안전성학회:학술대회논문집
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• 한국식품위생안전성학회 1994년도 방사선 조사 식품의 안전성 및 실용화에관한 국제심포지움
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• pp.1-11
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• 1994

• 한국식품저장유통학회:학술대회논문집
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• 한국식품저장유통학회 2003년도 제23차 추계총회 및 국제학술심포지움
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• pp.135.1-135
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• 2003

To elucidate the effect of gamma-irradiation on the molecular properties of hemoglobin, the secondary, tertiary structure, and the molecular weight size of the protein were examined after irradiation at 0.5, 1, 5, and 10 kGy. Gamma-irradiation of hemoglobin solutions caused the disruption of the ordered structure of the protein molecules, as well as degradation, cross-linking, and aggregation of the polypeptide chains. A SDS-PAGE study indicated that irradiation caused initial fragmentation of the proteins and subsequent aggregation due to cross-linking of the protein molecules. The effect of irradiation on the protein was more significant at lower protein concentrations. Ascorbic acid decreased the degradation and aggregation of proteins by scavenging oxygen radicals that were produced by irradiation. A circular dichroism study showed that irradiation decreased the helical content of hemoglobin with a concurrent increase of the aperiodic structure content. Fluorescence spectroscopy indicated that irradiation decreased the emission intensity that was excited at 280 nm.