• Preventive Nutrition and Food Science
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• 제14권3호
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• pp.226-232
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• 2009

The effects of UV-C irradiation on the quality characteristics of powdered foods, sunsik and misutkaru, were examined during storage, where samples were irradiated at doses of 27, 54, and 108 kJ/$m^2$, respectively. In addition, sunsik and misutkaru samples were inoculated with Enterobacter sakazakii as a pathogen and then irradiated at doses of 0.5, 1, and 5 kJ/$m^2$, respectively. After treatment, the sunsik and misutkaru samples were stored at $20^{\circ}C$. The microbiological data represented that populations of total aerobic bacteria, Bacillus cereus, and E. sakazakii were significantly (p<0.05) reduced with increasing UV-C doses. In addition, UV-C irradiation did not cause inferiority in the color quality of the samples during storage. Sensory evaluation results also indicated that there were no significant differences (p<0.05) among the irradiated samples. These results suggest that UV-C irradiation may be useful in maintaining the quality of sunsik and misutkaru during storage.

• 한국식품영양과학회지
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• 제28권1호
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• pp.40-46
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• 1999

Microbiological quality of commercial white ginseng was examined, together with investigation on its water absorption pattern and radiosensitivity of molds isolated from the samples. Comparative effects of phosphine fumigation and gamma irradiation on microbial control and disinfestation of the samples packed in a commercial laminated film and stored for six months at ambient(20oC, 70% RH) and accelerated(40oC, 90% RH) conditions were studied. Commercial white ginseng was contaminated with coliforms by 103~104CFU/g and molds by 102~104CFU/g and thus decontamination process was required for hygienic quality and storage stability. Phosphine fumigation showed no sterilizing effects on microbes contaminated, while gamma irradiation at around 5kGy was effective for decontaminating microorganisms, showing D10 values of 0.48~0.60kGy for isolated molds. Even though the storage insects, Plodia interpuctella Hubner and Lasioderma serricorne(cigarette beetle) were easily destroyed by phosphine fumigation, gamma irradiation less than 5kGy was found effective for both purposes to improve biological quality of stored white ginseng, thereby extending the storage life of packed samples resulting from increased critical moisture content by about 1%(Aw 0.76).

• 한국물환경학회지
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• 제26권6호
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• pp.1034-1039
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• 2010

Variation of formation potential of THM (THMFP) by chlorination of humic acid and characteristics of water quality with ${\gamma}$-ray irradiation were investigated, which were divided into two categories by the order of ${\gamma}$-ray irradiation and chlorination in water treatment process. The group A consisted of the ${\gamma}$-ray irradiation followed by chlorination process of humic acid, and the group B consisted of the chlorination followed by ${\gamma}$-ray irradiation process. The pH, ORP, $UV_{254}$, and DOC decreased rapidly with an increase in ${\gamma}$-ray irradiation of 3 kGy. while conductivity was little changed. Maximum degradation ratio of chloroform in THMs of group A was 82%, while that in group B was 69%. No brominated THMs were detected at high irradiation (>3 kGy). We found that group A water treatment process was more effective in lowering the THMFP than that of group B.

• 한국식품저장유통학회지
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• 제20권1호
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• pp.45-51
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• 2013

UV-C 및 전자선 조사에 의한 막걸리의 품질변화를 측정하기 위하여 생막걸리를 UV-C 및 전자선 조사하고 $4^{\circ}C$에서 15일간 저장하여 이에 따른 품질 변화를 측정하였다. UV-C 및 전자선 조사에 의한 미생물 분석 결과, 전자선 조사가 UV-C 조사보다 막걸리 내 미생물을 제어하는 데 더 효과적인 기술로 확인되었다. UV-C 또는 전자선 및 저장기간에 따라 pH가 증가하는 경향을 보였다. 산도 측정 결과, 저장기간에 따라 UV-C 및 전자선 조사군이 대조군보다 산도가 유의적으로 증가하는 경향을 보였다. 명도의 경우 UV-C 및 전자선에 의해 그 값이 증가하는 경향을 보인 반면 저장기간이 증가함에 따라 감소하는 경향을 보였다. 적색도는 전자선 처리군이 다른 처리군에 비해 높은 값을 보였으며, 저장기간에 따른 변화는 일관적이게 나타나지 않았다. 황색도는 UV-C 및 전자선 조사에 따른 변화는 일관적이지 않았으나 저장기간에 따라 값이 증가하는 경향을 보였다. 환원당 함량 측정 결과 저장 초기 UV-C 및 전자선 조사에 의해 함량이 높았으나, 저장기간에 따라 대조군에 비해 빨리 감소하였다. 따라서, 전자선 조사가 UV-C 조사보다 막걸리 내 미생물을 효과적으로 제어할 수 있다고 판단된다. 그러나 막걸리에의 UV-C 또는 전자선 조사로 인해 발생되는 품질변화를 최소화하기 위한 방법 및 UV-C 또는 전자선 조사에 의한 화학적 특성 변화의 규명에 대한 지속적인 후속연구가 필요할 것으로 판단된다.

• 한국식품저장유통학회지
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• 제6권1호
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• pp.23-28
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• 1999

Commercial red ginseng, which was manufactured for the past 6 years, showed a microbial level of 2.0${\times}$10\ulcorner to 7.2${\times}$10\ulcorner CFU/g of total aerobic bacteria and molds. The moisture content of commercial products was ranged from 13.54 to 17.26%, which were higher than that of the product standard, 14%. Irradiation of red ginseng at 2.5 kGy resulted in the reduction of microorganisms contaminated to below the detectable level. Irradiation prevented mold growth on red ginseng during storage at RH 90% and 25$^{\circ}C$; molds were found at the 72nd day after storage in 2.5 kGy-irradiated sample, while 41st day in the nonirradiated control. At this point of time, irradiated samples showed an increased level of moisture content required for mold growth, 22.2% in 2.5 kGy group and 21.5% in control group. Based on the above results, microbiological qualities of red ginseng could be effectively improved by the optimum dose of irradiation, which was expected to secure the quality stability of red ginseng during distribution under the high-moistured conditions.

• 한국식품영양과학회지
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• 제28권1호
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• pp.47-52
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• 1999

Comparative effects of phosphine fumigation and gamma irradiation were evaluated on the qualities of white ginseng prepacked in a commercial laminated film in terms of water absorption, Hunter color parameters(L, a, b) and organoleptic properties(overall color/appearance, flavor) during 6 months of storage at ambient(20oC, 70% RH) and accelerated(40oC, 90% RH) conditions. Moisture content of packed white ginseng(initial 8.44%) linearly increased with storage period, thereby reaching to about 10% (r=0.9966) in ambient and more than 15%(r=0.9886) in accelerated conditions, respectively, at the 6th month of storage. The storage at severe conditions resulted in remarkable changes in Hunter's color values, decrease in whiteness(L) and increase in redness(a) and yellowness(b), while both treatments, phosphine and irradiation less than 5kGy, did not cause any significant changes in color parameters. Phosphine fumigation was shown detrimental to overall flavor of white ginseng(p<0.01), however or ganoleptic qualities of stored samples were effectively maintained by irradiation less than 5kGy(p< 0.05). As the index on the guality of white ginseng stored at severe conditions its organoleptic quality was highly correlated with moisture content(r= 0.9777) and Hunter color values(over 0.9), suggesting the critical values of 15.5% moisture and 72.56, 7.15, 21.45 in Hunter's L, a, b values, respectively.

• 한국식품과학회지
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• 제18권6호
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• pp.427-430
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• 1986

살균처리(殺菌處理) 방법(方法)(ethylene oxide, gamma irradiation)에 따른 5가지 향신료와 그들을 혼합스-프로 가공하여 순위법으로 관능적 품질을 평가한 결과는 다음과 같다. 시료 모두가 무처리구, 방사선 조사(照射)구, E.O.처리구의 순(順)으로 선호도(選好度)를 나타내었고, 분산분석 결과 5가지 향신료 각각이 1%(<0.01)와 5%(p<0.05)수준으로 유의차가 있었으며 혼합가공된 것은 유의차가 인정되지 않았다. 따라서 Duncan의 다범위검정 결과 5가지향신료 모두가 무처리와 방사선 조사구간(照射區間)에는 유의성이 없었고, E.O.처리구간에는 1%와 5%수준의 유의차가 인정되어 살균을 위한 방사선 조사(照射)는 향신료의 품질에 영향을 미치지 않으나 E.O.처리구는 품질저하를 가져 옮을 알 수 있고 이러한 결과는 각 시료의 주요 이화학적(理化學的) 특성(特性)의 변화(變化)와 일치하였다.

• Current Research on Agriculture and Life Sciences
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• 제30권1호
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• pp.51-59
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• 2012

Fresh oyster mushrooms (Pleurotus ostreatus) were gamma-irradiated at 0, 1, 2, and 3 kGy. The effects on various quality attributes were determined during storage at $5{\pm}1^{\circ}C$. Color changes were more prominent in the cap region than the stem part. At the start of storage increase of Hunter's L-value (lightness) was observed in the caps of 2 and 3 kGy-irradiated samples. The L-value was higher in the all irradiated samples during storage. The trend was different in the case of stem region, where L-value decreased upon irradiation, but remained high throughout storage. The ${\alpha}$-value declined, whereas the b-value increased following irradiation. Irradiation showed a dose-dependent effect on the firmness, which was clearer during storage, but the samples irradiated at 1 kGy maintained an overall better texture than other irradiated samples. The weight loss was also higher in the all irradiated samples during storage. The samples irradiated at 1 kGy showed good physical appearance without any fungal attack at the end of storage; however color change in cap region was quite apparent. The ultra-structural drastic effect of irradiation was understandable using scanning electron microscopy. E-nose analysis demonstrated a clear change in the volatile profiles of all irradiated samples. Although the effect of irradiation on quality characteristics was quite clear but the all irradiated samples were free from fungal attack that was observed in the case of control sample.

• 한국식품영양과학회지
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• 제36권2호
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• pp.216-221
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• 2007

원부재료에 부착된 미생물을 김치제조 전에 오존 및 방사선 조사를 실시하여 미생물을 감균시키고 위생화된 재료로 김치를 제조하였을 때의 미생물학적, 화학적 및 관능적 변화를 측정하였다. 대조군 맛김치의 미생물 변화는 총균수의 경우, 저장기간이 증가할수록 빠른 속도로 증가한 후 저장 10일 이후부터는 서서히 감소하였다. 그러나 오존 및 방사선 처리군의 경우에서는 대조군에 비하여 서서히 증가하는 경향이었다. 젖산균수의 경우에는 대조군은 오존 및 방사선 처리군에 비하여 다소 낮은 변화를 보이는 것으로 나타났다. 효모 및 곰팡이수의 변화는 대조군이 가장 높은 균수를 저장기간 내내 유지하였으나 오존 및 방사선 처리군은 대조군보다 낮은 균수를 보였으며 그 변화는 3 kGy와 5 kGy가 가장 적은 것으로 나타났다. pH 및 산도의 변화에서도 대조군은 빠른 속도로 변화되었으나 오존 및 방사선 처리군의 경우는 서서히 변화되었으며 오존 및 방사선 처리군 중에서는 3 kGy와 5 kGy 처리군이 가장 변화가 적었다. 저장기간에 따른 관능검사 결과는 발효가 진행됨에 따라 대조군은 빠른 품질변화를 보였지만 오존 및 방사선 처리군은 발효의 진행이 서서히 일어나 품질 유지기간을 연장시키는 것으로 나타났다.

• 대한방사선기술학회지:방사선기술과학
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• 제11권1호
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• pp.33-41
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• 1988

This study was measured the radiation-induced current - X-ray dose, dose rate, X-ray quality, time, temperature, electric field characteristics and the dependence of gap length in insulating oil under of D.C. Voltage before, during and after X-ray irradiation. The obtained results can be summarized as following. 1. The radiation - induced current is more the dependence of X-ray quality (tube voltage) than quantity (tube current), the dependence of quantity is appeared at the high than low X-.ay tube voltage. 2. The dependence of dose rate is appeared at the more dose rate, and ${\triangle}\;=\;0.64{\sim}0.74$. 3. The higher temperature of insulating oil and X-ray tube voltage (X-ray quality) is increased, at the low electric field, the more radiation-induced current. 4. $G_{eq}-G_{o}(={\triangle}G)$ is increased at the low than high temperature, high than low X-ray quality. 5. The dependence of temperature is appeared before than during X-ray irradiation. 6. The RIC saturation region is appeared at the high than low insulating oil temperature during (1000 V/cm above) than before (4000 V/cm above) X-ray irradiation.