• Preventive Nutrition and Food Science
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• v.14 no.3
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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.

• Preventive Nutrition and Food Science
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• v.7 no.2
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• pp.195-200
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• 2002

Changes in accumulated pulsed photostimulated luminescene (PPSL) signals were observed after storage, which affected the ability to detect irradiation in black and white peppers. The PPSL curves were accumulated linearly during the 120 s measurement times, and PPSL signals increased according to irradiation doses. Threshold levels of black and white peppers were below 557$\pm$220 and 503$\pm$92 photon counts in 60 s, and below 679$\pm$351 and 812 $\pm$ 648 photon counts in 120 s, respectively. The PPSL signals of black and white peppers linearly increased with irradiation dose up to 5 kGy, but very little from 5~10 kCy. The accumulated PPSL signals of irradiated black and white peppers had higher decay rates when stored in normal room conditions than in a darkroom Detection of irradiation was possible for up to 12 months after irradiation, if the samples were stored in a darkroom.

• Food Science and Preservation
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• v.13 no.1
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• pp.55-60
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• 2006

Two kinds of composite seasoning products (beef broth powder, polk bone extract powder) were used for a detection trial of gamma irradiation treatment up to 10 kGy by analyzing photostimulated luminescence (PSL), electron spin resonance (ESR) and thermoluminescence(TL). PSL results showed that the photon counts of non-irradiated samples were lower than 700, while those of irradiated samples were higher than 5000, which makes it possible to screen irradiated composite seasoning products at 1 kGy or over from the non-irradiated control. ESR signals measured for both irradiated samples were not irradiation-specific, even though they were dose dependent in the signal intensity. Radiation-induced TL glow curves were found in irradiated beef broth powder and furthernmore, TL ratio $(TL_4/TL_2)$ obtained by a re-irradiation step could verify the detection result of TL1 glow curves, showing ratios lower than 0.05 in the non-irradiated sample and higher than 1.00 in irradiated ones.

• Korean Journal of Food Science and Technology
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• v.42 no.2
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• pp.136-141
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• 2010

This study attempted to determine whether Photostimulated Luminescence (PSL) is applicable for the detection of post-irradiated foods by measuring the PSL photon counts of unirradiated and irradiated dried spices and herbs. A total of 19 dried spices and herbs was irradiated with a $^{60}Co$ $\gamma$-ray source at 1, 5 and 10 kGy followed by measurement of PSL photon. The photon counts of unirradiated samples below 700 correspond to negative. Fifteen samples irradiated over 1 kGy showed photon counts of more than 5,000, indicating irradiation treatment. Intermediate counts (photon count 700-5,000) were observed in irradiated white/black pepper, nutmeg and cinnamon bark at 10 kGy. These results suggest that it is possible to detect whether dried spices and herbs were irradiated by analyzing PSL, with the exception of white/black pepper, nutmeg and cinnamon bark. Irradiated white/black pepper, nutmeg and cinnamon bark containing low levels of minerals were not sensitive to PSL. Therefore, further investigation is sugguested to be performed by Thermoluminescence (TL) analysis or another validated or standardized method.

• Journal of Dairy Science and Biotechnology
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• v.28 no.2
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• pp.13-18
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• 2010

Electron Spin Resonance (ESR) spectroscopy has been used to detect the presence of radiation-induced free radicals in biological samples since the mid 1950s and to irradiate foods containing cellulose, crystalline sugar, and bone. Therefore, we analyzed the ESR spectrum of irradiated infant formula and its ingredients in this study. Samples were irradiated with 2 different radiation sources of $^{60}Co$ gamma rays and electron beams (EBs), and the absorbed doses were 0, 1, 3, 5, and 7 kGy. ESR measurements were performed under normal atmospheric conditions using a JEOL JES-FA100 spectrometer equipped with an X-band bridge. Irradiated infant formula showed anunsymmetrical spectrum ($g_1$=2.0050, $g_2$=2.0006); in contrast, non-irradiated samples showed asymmetrical spectrum. The ingredients of irradiated samples showed a multi-component ESR signal in glucose and lactose and a singlet-type spectrum in milk powder (g=2.0050). $R^2$ of the dose-response curve showed a fine linearity of over 0.95 across the entire sample. We also compared the spectra of identical samples irradiated with $^{60}Co$ gamma rays and EBs, because EBs can be used for food irradiation in foreign countries, although this is not permitted in Korea. However, we could not find any significant differences according to the types of radiation source. Thus, ESR spectroscopy can be used to detect irradiated infant formula and several types of primary ingredients in this formula.

• Journal of Radiation Industry
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• v.4 no.3
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• pp.221-226
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• 2010

Physical detection methods, photostimulated luminescence (PSL), thermoluminescence (TL) and electron spin resonance (ESR) were applied to detect electron beam-irradiated agricultural products, such as red pepper, black pepper, raisin, walnut, beef seasoning and pistachio. The absorbed irradiation doses for representative samples were controled at 0, 1, 3, 5 and 10 kGy. PSL values for non-irradiated samples were <700 counts/60s (lower threshold, $T_1$) except beef seasoning, whereas those of irradiated samples were more than 5,000 photon counts, upper threshold ($T_2$) in black pepper, raisin, and beef seasoning and intermediates values of $T_1-T_2$ in red pepper, walnut, and pistachio. Minerals seperated from the samples for TL measurement showed that non-irradiated samples except pistachio (TL ratio, 0.12) were characterized by no glow curves situated at temperature range of $50{\sim}400^{\circ}C$ with TL ratio (0.01~0.08), while irradiated samples except pistachio at only 1 kGy (TL ratio, 0.08) indicated glow curve at about $150{\sim}250^{\circ}C$ with TL ratio (0.28~3.10). ESR measurements of irradiated samples showed any specific signals to irradiation. The samples of both red pepper and pistachio were produced specific signals derived from cellulose radicals as well as single line signals for black pepper and walnut, and multiple signals derived from crystalline sugar radicals for raisin and beef seasoning. In conclusion, The ESR methods can apply for detection of pistachio exposed to electron beam but PSL and TL are not suitable methods. Furthermore, TL and ESR suggeted that both techniques were more useful detection method than PSL to confirm whether red pepper, walnut and beef seasoning samples have been exposed to electron beam.

• Food Science of Animal Resources
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• v.25 no.1
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• pp.13-19
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• 2005

The radio-sensitivity of pathogens and the effect of irradiation on microbiologican safety and mutagenicity of meat products such as seasoned and cooked beef and ham were investigated. Samples were radiation-sterilized and inoculated at 10/sup 7/ cfu/g with each of the four pathogens including Salmonella typhimurium, Escherichia coli, Staphylcoccus aureus, and Listeria ivanovii. No viable cells of pathogens were observed in the sample irradiated with 3 kGy. The D/sub 10/ value of inoculated pathogens in seasoned and cooked beef and ham were 0.24∼0.48 and 0.39∼0.45, respectively. Results of Ames test performed with non-irradiated and irradiated seasoned and cooked beef and ham were both negative at the level of 625, 1,250, 2,500, 50,000, and! 10,000 ㎍ sample/plate, respectively. Results indicate that low dose (2∼3 kGy) irradiation is effective to ensure safety for seasoned and cooked beef and ham with toxicological wholesomeness.

• Journal of Community Nutrition
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• v.4 no.3
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• pp.180-186
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• 2002

The food attitudes of 285 Korean female students attending a secondary school in Seoul were examined with respect to the 5 food groups of the Korean Food Tower : grain products, vegetables and fruits, meat, milk, and fats and sweets. An instrument with 22 items was utilized to measure food attitudes toward the five food groups. The items were categorized into five factors through factor analysis to obtain a description of the participants' food attitudes. The five factors are conscious choice of food, health concerns, economics and time influence, interest in foods, and foods that energize. Several facts emerged from examining the food attitudes. The most evident was their response to the items concerning the influence of economics and time on food choice, which the majority consider not limiting their food consumption. Most participants gave favorable responses for vegetables and fruits on all the five factors, but gave unfavorable responses for meat group and fats and sweets in health concerns. They also gave favorable responses for“foods that energize”for all except fats and sweets. Four of the total 25 relationships among food intake (five groups) and food attitudes (five factors) were found to have significant positive correlations (p < .01). (J Community Nutrition 4(3) : 180∼186, 2002)

• Journal of Radiation Industry
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• v.6 no.4
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• pp.305-310
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• 2012

This study examined radiation detection properties of imported perilla seeds, almonds, and soybeans. Food samples were irradiated at doses of 0.5, 1, 2, and 4 kGy and analyzed by photo-stimulated luminescence (PSL), thermoluminescence (TL), and electron spin resonance (ESR). The results of PSL showed that photon counts of irradiated perilla seeds and soybeans were $32,959counts{\cdot}60sec^{-1}$ and $7,234counts{\cdot}60sec^{-1}$, respectively, at an irradiation dose of 0.5 kGy, and the photon count of irradiated almonds was $5,581counts{\cdot}60sec^{-1}$ at an irradiation dose of 1 kGy. The results of TL showed that this technique is useful for detecting irradiated samples; the TL ratios ($TL_1/TL_2$) measured for the food samples at an irradiation dose of 0.5 kGy were 0.2301 for perilla seeds, 0.4595 for almonds, and 0.4827 for soy beans. Lastly, results of ESR spectroscopy for only soybeans revealed specific signals derived from free radicals captured in the cellulose. In conclusion, PSL, TL, and ESR methods can be used for the detection of gamma-irradiated soybean samples, whereas gamma-irradiated perilla seeds and almonds can be confirmed by a serial detection with a TL method after PSL.

• Journal of Radiation Industry
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• v.6 no.3
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• pp.267-272
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• 2012

This study evaluated the change in anti-allergy activity of ${\beta}-glucan$ by electron beam irradiation. ${\beta}-Glucan$ was irradiated at dose of 50 kGy and then orally pre-treated with electron beam irradiated and non irradiated ${\beta}-Glucan$ for 7 days. After pre-treatment, allergy was induced by injection of ovalbumin (OVA). Serum total immunoglobulin E (IgE) and OVA-specific IgE levels in the allergic mice was significantly increased but the mice pre-treated 50 kGy electron beam irradiated ${\beta}-glucan$ was significantly decreased the levels of total IgE and OVA-specific IgE, respectively. Moreover, cytokine production (interleukin-4) was also decreased in the 50 kGy electron beam irradiated ${\beta}-Glucan$ pre-treated mice. These results indicate that pre-treatment of 50 kGy electron beam irradiated ${\beta}-glucan$ may elevate the anti-allergy activity. Therefore, electron beam-irradiated ${\beta}-glucan$ could be used for nutraceutical foods in food industry.