• Journal of Radiation Industry
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• v.7 no.1
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• pp.15-21
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• 2013

The detection characteristics of irradiated spices were investigated depending on radiation sources and doses by photostimulated luminescence (PSL) and Thermoluminescence (TL). 6 kinds of spices (turmeric, onion powder, red pepper, basil, parsley, black pepper) were irradiated at 0 to 10 kGy under ambient conditions by both a $^{60}Co$ gamma irradiator and an electron beam (EB) accelerator, respectively. The PSL analysis showed negative results for non-irradiated spices, while irradiated spices gave intermediate and positive value, which presented the limited potential of PSL technique. In TL measurement, TL glow curves on non-irradiated samples appeared at about $300^{\circ}C$ with low intensity. All irradiated samples were easily distinguishable through radiation-specific strong TL glow curves with maximum peak in range of $150{\sim}200^{\circ}C$. TL ratio ($TL_1/TL_2$) obtained by a re-irradiation step could verify the detection result of $TL_1$ glow curves, showing ratios lower than 0.1 in the non-irradiated sample and higher than 0.1 in irradiated ones. Therefore, in PSL measurement, the identification of irradiated spices showed more clear results in electron beam irradiated samples. TL analysis showed obvious difference between non-irradiated and irradiated samples in gamma ray and electron beam irradiated samples.

• Journal of Food Hygiene and Safety
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• v.28 no.3
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• pp.258-266
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• 2013

This study was conducted to determine the PSL and TL properties of foods irradiated with electron beam and gamma-ray. 5 kinds of food including cereal, pulse, fish powder, dried vegetable and tea were irradiated at 0 to 10 kGy by electron beam accelerator or $^{60}Co$ gamma-ray irradiator. The PSL analysis showed negative results for most of the non-irradiated samples. Non-irradiated shrimp powder showed intermediate result. Irradiated samples gave negative or intermediate or positive value which presented the limitation of PSL technique. In TL analysis, there were TL glow curves at around $300^{\circ}C$ with low intensity on non-irradiated samples. Maximum peak in the range of $150-250^{\circ}C$ was appeared on irradiated samples. TL ratio obtained by re-irradiation with 1 kGy was less than 0.1 on non-irradiated samples and higher than 0.1 on irradiated samples. Therefore, in PSL measurement, electron-beam irradiated samples could obtain more clear results. TL analysis showed obvious difference between non-irradiated and irradiated samples. But the identification was impossible for the sample of rice and lemon tea. Because of it's low contents of mineral.

• Korean Journal of Food Science and Technology
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• v.48 no.5
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• pp.399-404
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• 2016

The applicability of photostimulated-luminescence (PSL) and thermoluminescence (TL) for the detection of 12 food materials (potato, onion, garlic, dried pumpkin, black mushroom, black soybean, Cheongkukjang powder, sea mustard, pepper powder, Ramyun soup, corn tea, and green tea powder) irradiated with an electron beam, gamma ray, and X ray at a range of 0.15 to 10 kGy was investigated. For PSL, negative results (less than 700 photon counts (PCs)) were observed from non-irradiated foods while the irradiated foods showed intermediate (879 to 2,414 PCs) and/or positive (19,951 to 65,919,035 PCs) values. In all irradiated samples, the maximum peak of the TL glow curve was observed between 150 and $250^{\circ}C$. Our findings demonstrate the successful application of PSL and TL to determine whether food items were irradiated or not. However, there were no significant differences among the radiation sources.