• Preventive Nutrition and Food Science
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• 제8권1호
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• pp.85-88
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• 2003

Effects of irradiation on color removal, tyrosinase inhibition, xanthine oxidase inhibition and nitrite scavenging capacity of Lonicera japonica extracts were evaluated. Lonicera japonica extracts were irradiated at 10, 20, and 30 kGy. Hunter color $L^{*}$- and $a^{*}$-values increased but $b^{*}$-values decreased dose-dependently following irradiation. The extracts were potent inhibitors of tyrosinase and xanthine oxidase. Tyrosinase inhibition was higher in the irradiated sample than non-irradiated, and subsequently increased with increasing irradiation doses. The extracts had a higher inhibitory effect against xanthine oxidase, and the effect was not changed by irradiation. Nitrite scavenging capacity was the highest in the extract at pH 1.2, and was not significantly affected by irradiation. These results indicate that gamma irradiation may not influence the biological activities of Lonicera japonica extracts when irradiated up to 30 kGy. Furthermore, color of the extracts can be improved to have improved applicability for the food and cosmetic industries without any adverse change in biological functions.ons.s.

• Preventive Nutrition and Food Science
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• 제14권4호
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• pp.362-366
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• 2009

To determine the effect of electron-beam irradiation on the contents of polymethoxylated flavones (PMFs) extracts from citrus pomaces (CP), CP was irradiated at 0, 1, 2, or 5 kGy. Methanol extract of the irradiated CP were prepared and the PMF (nobiletin, sinensetin, and tangeretin) content of the extract was determined. Nobiletin and sinensetin of CP extract significantly increased with irradiation dose-dependent. However, electron-beam irradiation decreased the amount of tangeretin in the CP extract. These data suggest that irradiation can liberate phenolic compounds such as nobiletin or sinensetin, but tangeretin might have different pathway of conversion by irradiation. Therefore, irradiation can be a tool to change the composition of PMFs in CP.

• Preventive Nutrition and Food Science
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• 제7권2호
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• pp.184-187
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• 2002

Blood products from slaughterhouses that are not hygienically prepared for disposal or food consumption pose a human health hazard. Gamma irradiation is an effective method for sterilization of blood products, but may introduce changes in the molecular characteristics of proteins. This study evaluated the effects of irradiation on animal plasma proteins. Bovine and porcine blood was obtained from a slaughterhouse and the plasma proteins purified and lyophilized. The secondary structure and molecular weight distribution of the plasma protein solutions and powders were examined after ${\gamma}$-irradiation at 1, 5, 7 and 10 kGy. Gamma-irradiation affected the molecular properties of the protein solutions, but not the protein powders. Circular dichroism and sodium dodecyl sulfate-polyacrylamide gel electrophoresis studies showed that increased doses of ${\gamma}$-irradiation decrease the ordered structure of plasma proteins in solution, and cause initial fragmentation of the polypeptide chains and subsequent aggregation.

• Preventive Nutrition and Food Science
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• 제8권4호
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• pp.343-348
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• 2003

To elucidate the effect of gamma-irradiation on the physicochemical properties of zein films, the molecular and mechanical properties of the films were examined after irradiation at various irradiation doses. Gamma-irradiation of zein solutions caused the disruption of the ordered structure of the zein molecules, as well as degradation, cross-linking, and aggregation of the polypeptide chains based on an SDS-PAGE study. Gamma-irradiation increased the solubility of zein and decreased the viscosity due to cleavage of the polypeptide chains. Protein solubility of the zein films in urea/2-mercaptoethanol also increased with increasing irradiation doses. Alterations of the zein molecules by irradiation decreased water vapor per-meability by 12% and increased the elongation of zein films. However, mean tensile strength of the zein films was decreased by gamma-irradiation treatment. Measurement of Hunter color values indicated that irradiation caused a destructive effect on yellow pigments, resulting in a significant decrease in Hunter b values. The microstructure as observed by scanning electron microscopy showed that irradiated zein film had a smoother and glossier surface than the non-irradiated films.

• Preventive Nutrition and Food Science
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• 제2권1호
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• pp.23-28
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• 1997

Physicohemical properties of corn starches isolated from non-glutinous and corn grains fol-lowing γ-irradiation up to 10kGy were investigated. Blue value, water binding capacity and swelling power decreased, while alkali number ad solubility increased by γ-irradiation , which was more pronounced in glu-tinous corn starch than in non-glutinous corn starch. The optical transmittance increased with an increment of heating temperature and applied irradiation doses. No significant difference was observed in Hunter's color value between both starches isolated from non- irradiated and irradiated and irradiated corn grains. Amylograph viscosities decreased remarkably as dose levels increased. The overall effects of γ-irradiation was more distinguished in glutinous starch than in non-glutinous starch.

• 한국식품과학회지
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• 제30권3호
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• pp.581-589
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• 1998

$5{\sim}10\;kGy$ 범위의 감마선 조사는 한방약재에 오염된 유기체를 완전사멸 시켜 저장중 미생물학적 품질 안전성을 가져왔으며, 한방약재의 유효성분 추출율을 약 $5{\sim}25%$ 증대시킬 뿐만 아니라 추출시간의 단축효과도 나타냈다. 또한 살균 및 유효성분의 추출율이 증대된 조사선량에서 한방약재의 몇 가지 생리적 활성(항산화력, 항보체능력, 아질산염 소거능, 전자공여능)은 비조사군과 차이를 보이지 않았다.

• Preventive Nutrition and Food Science
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• 제2권2호
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• pp.89-95
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• 1997

The comparative effects of gamma irradiation an ozone treatment on the microbiological and physicochemical qualities were investigated for the improvement of hygienic quality of aloe powder and bee pollen. Gamma irradiation at 7.5~10kGy could reduce total aerobic bacteria, molds and coliforms below detection levels, but ozone treatment up to 18 ppm for 8hr was not sufficient to eliminate the microorganisms from aloe powder and bee pollen. The physicochemical properties such as fatty acid an amino acid compositions, mineral content, TBA value, barbaloin and pigment contents were not significantly changed by gamma irradiation, whereas ozone treatment caused significant changes in fatty acid composition, lipid oxidation and destruction of barbaloin and natural pigments.

• 식품과학과 산업
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• 제53권3호
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• pp.264-276
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• 2020

Ionizing radiation is one of the efficient non-thermal pasteurization methods. The US Food and Drug Administration (FDA) allows the use of ionizing radiation to a dose up to 10 kGy for controlling foodborne pathogens and extending the self-life of foods. Recently X-rays, generated on absorption of high energy electrons in an appropriate metal target, have been used commercially for sterilization purposes. X-rays have the advantages of higher penetration power than E-beams and absence of harmful radioactive sources, such as Cobalt-60 or Cesium-137 associated with gamma-rays. That is why it has continued to receive attention as an attractive alternative to gamma-ray or E-beam irradiation. In this article, the potential of X-ray irradiation for controlling foodborne pathogens in various food products and necessary pre-requisite knowledge for the introduction of X-ray irradiation to the Korean food industry will be provided.

• Preventive Nutrition and Food Science
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• 제10권2호
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• pp.140-144
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• 2005

This study was carried out to establish methods for irradiation detection of irradiation in Korean wheat flour by pulsed photostimulated luminescence (PPSL) and viscometric methods. The photon counts of the irradiated Korean wheat flour measured by PPSL immediately after irradiation increased with increasing irradiation dose. The photon counts in the irradiated Korean wheat flour almost disappeared with lapse of time after storage in normal room conditions, but irradiation detection was still possible after 6 months in darkroom conditions. All irradiated samples indicated a decrease in viscosity with increasing stirring speeds (rpm) and irradiation doses. Irradiation at 1 kGy significantly decreased the viscosity. Consequently, these results suggest that the detection of irradiated Korean wheat powder is possible by both viscometric and PPSL methods.

• 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