• Journal of the Korean Society of Food Science and Nutrition
• /
• v.30 no.6
• /
• pp.1076-1081
• /
• 2001

Gamma-irradiated peanuts, Korean and Chinese origins, were investigated on detection properties by thermoluminescence (TL), electron spin resonance (ESR), and DNA comet assay (single cell gel electrophoresis). TL measurement showed that the non-irradiated sample revealed a glow curve with low intensity at about 25$0^{\circ}C$, while the irradiated samples showed higher intensity around at 18$0^{\circ}C$. TL ratio (TL$_1$/TL$_2$) of area for TL$_1$ glow curve to TL$_2$ was below 0.05 for the non-irradiated sample and 0.2 or more for the irradiated ones, thus identifying each other. ESR spectroscopy for the irradiated peanuts using outer skin showed negligible signals induced by irradiation, indicating ESR is little applicable to the detection of irradiated peanuts. In DNA comet assay, the non-sample had no or very short tails, whereas the irradiated samples revealed the cells with long tails. Significance in the increase of their lengths depending on irradiation dose (r=0.761/Korean, r=0.768/Chinese) was also found. There was no remarkable difference in detection properties by origins of samples in all determinations, It is concluded that TL analysis or DNA comet assay is suitable for detection of irradiated peanuts and a combined method is recommendable for enhancing the reliability of detection results.

• Journal of the Korean Society of Food Science and Nutrition
• /
• v.40 no.6
• /
• pp.824-831
• /
• 2011

This study was to investigate 90-day repeated-dose toxicities of 50 kGy irradiated methanol extract powder of red ginseng in ICR mice. The test materials (methanol extract powder of red ginseng with or without 50 kGy irradiation) were administered by gavage to male and female ICR mice at dose levels of 0, 125, 250 and 500 mg/kg/day for 90 days. In the results, no abnormality was observed in mortality, clinical findings, body weight changes, food consumptions, opthalmoscopic findings, necropsy findings and histopathological findings. Although the minor changes in blood and biochemical parameters were observed, they were not dose dependent and not affected by gamma irradiation. In conclusion, 90-day repeated oral dose of the methanol extract powder of red ginseng and 50 kGy irradiated methanol extract powder of red ginseng to ICR mice did not cause apparent toxicological change at the dose of 125, 250 and 500 mg/kg body weight.

• Journal of Food Hygiene and Safety
• /
• v.4 no.2
• /
• pp.119-132
• /
• 1989

Gamma irradiation as a new physical treatment was applied to comparative investigates with a conventional ethylene oxide fumigant on the microbiological and physicochemical qualities of selected spices and dry vegetables such as powdered red pepper, black pepper, welsh onion, onion, garlic, carrot, korean cabbage and instant ramyon soup. The microorganisms contaminated in the sample, including total viable count, thermophilic bacteria, aerobic spore and fungi counts between the $10^4\;to\;10^6/g$ range. Coliforms were found only in black pepper and welsh onion powder as the $10^2\;to\;10^3/g$ level. A radiation dose of 7 to 10 KGy were sterilized completely to the contaminated microorganisms, while ehthylene oxide (E.O.) fumigation reduced of them to the $10^3/g$ level. An optimum dose of irradiation was less detrimental than E.O. fumigation to the physicochemical properties of the sample. Sensory evaluation after three months of storage at room temperatures showed that the overall acceptability of irradiated sample was higher than that of the non treated control as well as E.O. fumigated samples. Comparison gamma irradiation with E.O. gas treatment showed that E.O. treatment was less effective than radiation in cotrolling microbial contamination of spices and vegetables.

• Journal of the Korean Society of Radiology
• /
• v.15 no.2
• /
• pp.247-255
• /
• 2021

The purpose of this study was to examine the radiation protection effect of protaetia brevitarsis larvae extracts known as antioxidant food. In this study 90 female rats were clssified in to 5 groups: NC Group, PBE Group, IR Group, PBE+IR Group and IR+PBE Group. In IR Group, 7 Gy of Co-60 gamma ray was irradiated to SD rat and protaetia brevitarsis larvae extracts were administered orally at 200 mg/kg once a day for 14 days. And then on the 1 day, 7 days, 21 days later after irradiation, changes in blood cell component, superoxide dismutase(SOD) activity, spleen index, histopathological evaluation of the ovary and uterus were observed. As a result, the PBE+IR Group (p<0.01, p<0.05) and IR+PBE Group (p<0.01, p<0.01) showed a significantly radiation protection than the IR Group in lymphocyte and red blood cell on the 21 days. It was also confirmed that SOD activity of PBE+IR Group (p<0.01) and IR+PBE Group (p<0.01) was significantly increased than the IR Group. In spleen index, PBE+IR Group (p<0.05) and IR+PBE Group (p<0.01) showed a significantly recovery than the IR Group. In histopathological observation, PBE+IR Group in the ovary and PBE+IR, IR+PBE Group in the uterus showed less inflammatory reactions of cystoplasm than the IR Group. Based on These results, It is judged that protaetia brevitarsis larvae Extracts have radiation protection effect against blood and reproductive. It is expected to be useful for research of radiation protection agent.

• Food Science and Preservation
• /
• v.16 no.2
• /
• pp.186-191
• /
• 2009

An electron beam or gamma-rays(0-5 kGy) were applied to two popular commercial sprout seeds, those of radish and red cabbage, and both physiological and microbiological qualities during germination were examined. Total bacterial counts of radish and red cabbage seeds were 5.02 and 2.86 log CFU/g, respectively, and were reduced by 2-3 logs after irradiation, but nonirradiated and irradiated samples showed similar microbial populations on day 5 after germination, although day 3 levels of irradiated samples were $23{\pm}2%$ lower. Coliforms were absent in both seed types. However, they were detected from the first day of germination, and rose to 4-5 log CFU/g on the fifth day. Coliforms were reduced by about 1-2 log CFU/g in 1 kGy-irradiated samples and were absent in the samples irradiated at 3 kGy. Irradiation at 1 and 3 kGy decreased germination by about 7% and 18%, respectively. Sprout yield and length were also significantly affected by irradiation, with no apparent difference between samples treated with the electron beam and gamma-rays.

• Korean Journal of Food Science and Technology
• /
• v.34 no.1
• /
• pp.18-23
• /
• 2002

The detection characteristics of gamma-irradiated $(0{\sim}4\;kGy)$ soybeans produced in Korea and China were investigated by thermoluminescene (TL), electron spin resonance (ESR), and DNA comet assay. The TL glow curves were shown at around $200^{\circ}C$ for irradiated soybeans, while that at $280^{\circ}C$ for the non-irradiated one. The normalization with a re-irradiation step at 1 kGy could verify the above detection results. The Korean soybean showed higher glow curves than Chinese did. The ESR spectroscopy for husks of irradiated soybeans revealed specific signals (g = 2.02374, 1.98715) derived from cellulose radical, which intensities were proportional to irradiation does, with the higher peaks in Chinese sample than Korean one. The DNA comet for the non-irradiated sample showed no or little tails, while those for irradiated samples above 0.5 kGy were remarkably changed in their length, size, and concentration, thus resulting in distinguishing non-irradiated from irradiated samples. As a result, TL, ESR, and DNA comet determinations were found suitable for the detection of irradiated soybean at 0.5 kGy or more, and negligible differences were observed between Korean and Chinese origins in their detection characteristics.

• Journal of the Korean Society of Food Science and Nutrition
• /
• v.32 no.1
• /
• pp.1-7
• /
• 2003

Radiation induced markers were investigated for the detection of irradiated oranges imported from America. In the DNA comet assay, the non-irradiated and irradiated samples showed the comets with long tails in both seed and flesh. Though this tendency was maintained for 6 weeks, identification of non-irradiated or irradiated samples was impossible. In the thermoluminescence (TL) measurement, the non-irradiated samples revealed a glow curve with low intensity at about 28$0^{\circ}C$, while the irradiated samples showed with higher intensity at around 18$0^{\circ}C$. There were no remarkable changes in detection properties for 6 weeks after irradiation. The TL ratio of area for TL$_1$ glow curve to TL$_2$ was below 0.1 for the non-irradiated samples and 0.5 or more for the irradiated ones during storage. In the electron spin resonance (RSR) measurement, irradiated oranges showed an unspecific central signal in all parts (seed, flesh and peel), so the detection for radiation treatment of oranges was impossible. Based on the results, DNA comet assay and ESR were not useful for the detection, but TL was appropriate to search radiation induced markers of oranges during storage period. The detectable period during storage is confirmed by sensory evaluation.

• Journal of Food Hygiene and Safety
• /
• v.38 no.5
• /
• pp.287-296
• /
• 2023

Mushroom consumption is gradually growing annually worldwide for many centuries. Oyster mushrooms (Pleurotus ostreatus), button mushrooms (Agaricus bisporus), and enokitake (Flammulina filiformis) are mainly consumed in Korea. However, mushrooms can be contaminated with pathogenic microorganisms, such as Listeria monocytogenes, because antibacterial treatment during mushroom cultivation and processing is insufficient. Therefore, many cases of mushroom contamination-related foodborne illnesses and food recalls have been reported. Three representative treatments are used to prevent microbial contamination in mushrooms: chemical, physical, and combination treatments. Among the chemical treatments, chlorine compounds, peroxyacetic acid, and quaternary ammonium compounds are commercially used and ozone and electrolyzed water has recently been used. Additionally, physical treatments, including ultrasound, irradiation, and cold plasma, are being developed. Combination techniques include ultraviolet/chlorine compounds, ozone/organic acid, and ultrasound/organic acid. This review describes the domestically consumed mushroom types and their characteristics, and investigates the mushroom contamination levels. Additionally, effective antibacterial technologies for reducing microbial contamination in mushrooms are also discussed.

• Food Industry And Nutrition
• /
• v.10 no.2
• /
• pp.26-31
• /
• 2005

천연물 유래 기능성 물질 탐색의 일환으로 녹차 추출물의 산업적 적용을 용이하게 하기 위하여 감마선 조사를 병용하여 추출물의 색도 및 라디칼 소거능을 확인하고, 이 추출 파우더를 돈육 패티에 적용하여 항산화, 색도 및 관능검사를 통해 기호도를 조사하였다. 생리활성을 가지는 녹차 잎 추출물의 라디칼 소거능은 $68.2\%$를 나타냈으며, 20 kGy로 조사했을 경우 비조사구와 큰 차이를 나타내지 않았다. 또한, 감마선조사에 의한 색도의 변화는 감마선 조사 후 $L^{\ast}-value$는 증가했고, $a^{\ast}$- 및 $b^{\ast}-value$는 감소하는 것으로 확인되었다. 또한, 녹차 잎 추출 파우더를 돈육 패티에 적용해본 결과 비첨가구에 비해 라디칼 소거능 및 지질 산화를 지연시키며, 조사된 녹차 잎 추출 파우더를 첨가한 돈육패티가 비첨가구 혹은 비조사된 녹차 잎 첨가구에 비해 저장 기간에 따라$L^{\ast}-value$가 높게 나타났다. 또한, 모든 처리구에서 관능적으로도 큰 차이를 보이지 않았다 그러므로 천연물 유래 녹차 추출물 파우더는 돈육 패티의 기능성 첨가제로서 우수하며, 감마선 조사는 녹차 잎 추출 파우더의 산업적 적용을 용이하게 하는 방법 중의 하나라고 사료된다.

• Korean Journal of Food Science and Technology
• /
• v.16 no.3
• /
• pp.319-321
• /
• 1984

Black pepper powder was irradiated at dose of 3,6 and 9 kGy, stored at ambient temperature in order to investigate the effect of irradiation on their microbial sterilization and physicochemical properties. Total and coliform bacteria were sterilized by irradiation up to 9 kGy and 3 kGy, respectively, and they were not grown until the end of storage period. $D_{10}$ value of total bacteria were in the range of 1.39-1.49 kGy. Proximate composition was not significantly changed according to the increase of irradiation dose except slight increase of the reducing sugar. The yield of volatile oil was slightly decreased by the increase of irradiation dose.