• Title, Summary, Keyword: thermoluminescence (TL)

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Detection of Irradiated Potato and Garlic by Thermoluminescence Measurement (Thermoluminescence 측정에 의한 감자와 마늘의 방사선 조사유무 확인)

  • Chung, Hyung-Wook;Kwon, Joong-Ho
    • Korean Journal of Food Science and Technology
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    • v.30 no.2
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    • pp.283-287
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    • 1998
  • Potato and garlic irradiated with gamma ray and electron beam at sprout-inhibition doses, 0.15 and 0.30 kGy were subjected to the detection whether they are irradiated or not by measuring thermoluminescence(TL) for the minerals adhering to the samples. Minerals extracted from the samples showed a high correlation coefficients between absorbed doses and corresponding TL responses. Nonirradiated samples, however, did not exhibit characteristic TL glowcurves. Major glowcurve peaks were observed at 200 to $260^{\circ}C$ in all irradiated samples. TL intensity was proportional to irradiated doses, but it varied with the samples tested even at the same dose. It can be concluded from the results that detection of irradiated potato and garlic is possible by measuring TL for extracted minerals from the unknown samples.

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Identification Characteristics of Irradiated Dried Red Pepper during Storage by Analysis of Thermoluminescence, DNA Comet, and DEFT/APC (Thermoluminescence, DNA Comet 및 DEFT/APC 분석에 의한 방사선처리 건고추의 저장 중 검지 특성)

  • Kim, Byeong-Keun;Kwon, Joong-Ho
    • Korean Journal of Food Science and Technology
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    • v.36 no.6
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    • pp.851-856
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    • 2004
  • Minerals separated from irradiated dried red pepper (whole) at 2.5 kGy or higher showed typical thermoluminescence (TL) glow curves ($TL_1$) at around $150^{\circ}C$, which increased with irradiation dose. The TL ratio ($TL_1/TL_2$) through re-irradiation step at 1 kGy enhanced reliability of TL identification results. DNA comet assay indicated that the intact cell was observed in non-irradiated pepper (seed), while some long tails were found in irradiated ones, showing relationship between irradiation dose and tail length. Log DEPT/APC values increased in proportion to irradiation doses in powdered and whole peppers. Based on overall results, irradiated dried red peppers could be screened using DNA comet assay or log DEFT/APC, and moreover the identification results were verified by TL analysis.

The Use of Pulsed Photostimulated Luminescence (PPSL) and Thermoluminescence (TL) for the Detection of Irradiated Perilla and Sesame Seeds

  • Yi, Sang-Duk;Woo, Si-Ho;Yang, Jae-Seung
    • Preventive Nutrition and Food Science
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    • v.5 no.3
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    • pp.142-147
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    • 2000
  • To establish a detection method of irradiated perilla and sesame seeds, studies were performed with pulsed photostimulated luminescence (PPSL) and thermoluminescence (TL). The PPSL photon counts of the mineral separated from irradiated sesame and perilla seeds were higher than unirradiated one and exhibited an increase with increasing irradiation dose and mineral content. Also TL intensities of minerals separated from irradiated sesame and perilla seeds increased with increasing irradiation dose. In all samples, detection was possible with shapes and maximum TL temperatures of the second glow curves showing lower regions than those of the first glow curves and correctly classified as irradiated samples. Glow curve ratios of irradiated samples were higher than 0.5. These results suggest that PPSL and TL are applicable methods for the detection of irradiated perilla and sesame seeds.

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Identification of Irradiated Granule-Type Ramen Soup Powder by Pulsed Photostimulated Luminescence and Thermoluminescence during Storage

  • Yi, Sang-Duk;Yang, Jae-Seung;Kim, Dong-Woo;Shin, Doo-Ho;Jo, Gab-Yeon;Chang, Kyu-Seob;Oh, Man-Jin
    • Preventive Nutrition and Food Science
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    • v.8 no.1
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    • pp.79-84
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    • 2003
  • This study was carried out to establish a method for determining if granule-type Ramen soup powder has been irradiated. Thermoluminescence (TL) and pulled photostimulated luminescence (PPSL) were used as the detection methods through observed changes of TL and PPSL intensities after storage under differing conditions. PPSL intensities increased with increases in irradiation doses. The threshold level of PPSL was below 412$\pm$58 photon counts regardless of storage conditions (room and darkroom) after 10 months. TL intensities also increased with increasing irradiation doses. The coefficients ($R^2$) of PPSL (0.74~0.94) and TL intensities (0.92~0.58) were very highly correlated with irradiation dose. The PPSL and TL intensities were decreased after 10 months of storage. These results indicate that discrimination of irradiated from non-irradiated granule-type Ramen soup powder is possible using TL and PPSL methods despite the decrease in intensities of TL and PPSL with increasing storage times.

Thermoluminescence (TL) of Minerals Separated from Irradiated Mussel

  • Yi, Sang-Duk;Oh, Man-Jin
    • Preventive Nutrition and Food Science
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    • v.10 no.1
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    • pp.17-21
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    • 2005
  • This study was carried out to determine whether detection of minerals separated from irradiated mussel could be could be done by thermoluminescence (TL) method. After the minerals were separated by sodium polytungstate solution (2.0 g/mL) from irradiated mussel, organic compounds remaining in the minerals were removed by acid-base treatment and dried at 50℃ overnight, and then the minerals were measured through TL. The TL intensities of separated minerals at different irradiation doses during storage conditions of room and darkroom were obtained. TL intensity of first glow curves for minerals separated from irradiated mussel showed linear increase from the control to 5 kGy and slight increase from 5 kGy to 10 kGy. Since glow curve ratios of G2, G3 and G4, calculated from re-irradiated minerals measured immediately after irradiation and after storage of three months were over 0.5, detection of irradiation was possible. G1, which showed the glow curve ratios above 0.1, was classified as non-irradiated samples because the unique first glow curve was not found within the recommended temperature interval (150-230℃). Hence, on the basis of TL intensity, and glow curve ratio and shape, it is possible to correctly identify irradaited mussels after mineral separation during storage.

Properties of PSL, TL, and ESR to Identify the Irradiated Sesame Seeds after Steaming

  • Lee, Jeon-Geun;Kausar, Tusneem;Chung, Hyung-Wook;Jeong, Il-Yun;Bhatti, Ijaz A.;Kwon, Joong-Ho
    • Food Science and Biotechnology
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    • v.18 no.2
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    • pp.374-378
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    • 2009
  • Three physical methods, photostimulated luminescence (PSL), thermoluminescence (TL), and electron spin resonance (ESR), have been applied to detect the irradiation treatment for the non- and steamed sesame seed samples. PSL successfully screened the irradiated samples from the non-irradiated control by comparing their photon counts (PCs) with the lower (less than 700 count/60 sec) and upper threshold values (higher than 5,000 count/60 sec). TL signals were still detected in all irradiated samples even after steaming, which was reconfirmed with TL ratios [integrated area of $TL_1$ (the first glow)/$TL_2$ (the second glow)] through re-irradiation step. ESR spectrometry showed that radiation-induced cellulose radicals were detected in all the irradiated samples irrespective of steaming treatment. Identification of the irradiated sesame seeds was possible even after steaming by analyzing PSL, TL, and ESR.

Detection Characteristics of Irradiated Dried Vegetables by Analyzing Photostimulated Luminescence (PSL) and Thermoluminescence (TL) (물리적 방법(PSL, TL)을 이용한 방사선 조사 건조 채소류의 검지)

  • Kim Mi-Yeung;Kim Byeong-Keun;Kim Kyo-Youn;Bhatti Ijaz A.;Kwon Joong-Ho
    • Korean Journal of Food Preservation
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    • v.13 no.2
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    • pp.211-215
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    • 2006
  • Photostimulated luminescence (PSI) and thermoluminescence (TL) were analyzed for dried vegetables irradiated at 0, 1, 4 and 7 kGy, such as dried oak mushroom, spinach, radish leaves, water cress, radish, and pumpkin, to detect irradiation treatment. PSL results that photon counts for non-irradiated samples were lower than 700 that corresponds to negative, while those of irradiated samples over 1 kGy showed positive photon counts$(\geq5000)$, indicating irradiation treatment Meantime, TL ratio by normalization was lower than 0.021 in threshold value for non-irradiated samples and more than 0.653 for irradiated samples, and therefore it was possible to detect whether the 6 kinds of dried vegetables were irradiated or not by analyzing PSL and TL.

Detection of Post-Irradiation of Dry Soup Base Ingredients in Instant Noodle by Thermoluminescence Technique (라면 건조 수프 재료의 방사선 조사 검지를 위한 Thermoluminescence 활용)

  • Hwang, Keum-Taek;Byun, Myung-Woo;Wagner, Ute;Dehne, Lutz I.
    • Korean Journal of Food Science and Technology
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    • v.30 no.4
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    • pp.759-766
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    • 1998
  • It was determined whether thermoluminescence (TL) technique is a potential method to detect post-irradiation of dry soup base mix for instant noodle and its ingredients. The ingredients or the mixtures were irradiated, from which minerals were isolated using sodium polytungstate solution. Their TL signals (1st glow TL intensity/2nd glow TL intensity reirradiated at 48.6 Gy) were measured. The TL signals in temperature ranges of $229{\sim}295^{\circ}C$ and $229{\sim}361^{\circ}C$ showed larger differences between unirradiated and irradiated samples compared to other ranges. The average TL signals for unirradiated garlic powder, ginger powder, black pepper powder, onion powder, red pepper powder, and sesame seeds were below 0.2, while those for onion powder, red pepper powder, and sesame seeds irradiated at 10 kGy were over 20 in the two temperature ranges. The average TL signals for unirradiated soup mixture were 0.08 and 0.1, respectively, in the two temperature ranges, while those for the mixtures containing 10 kGy-irradiated onion powder, red pepper powder, and sesame seeds individually or in combination were over 7. The average TL signals for the mixtures irradiated 1, 5, and 10 kGy were over 10.

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Identification of Bulgogi Sauce Added with Low Quantity of Electron Beam-Irradiated Garlic Powders by Thermoluminescence Analysis: An Inter-Laboratory Study (전자선 조사 처리한 마늘분말 첨가 불고기소스의 혼합비와 살균처리에 따른 열발광 판별특성: 실험실 교차 검증시험)

  • Ahn, Jae-Jun;Lee, Jeongeun;Baek, Ji-Yeong;Jeong, Il-Yun;Kwon, Joong-Ho
    • Journal of the Korean Society of Food Science and Nutrition
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    • v.42 no.11
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    • pp.1857-1863
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    • 2013
  • Bulgogi sauces containing electron beam-irradiated garlic powder (1%, 3%, and 5%) were used to compare their irradiation status before and after pasteurization ($85^{\circ}C$, 30 min), using a thermoluminescence (TL) analysis by two different laboratories. The sauces with non-irradiated ingredient only provided a background TL glow curve with a maximum peak after $300^{\circ}C$. However, the presence of irradiated ingredient (1 and 10 kGy) was evident through the typical TL glow curves in a temperature range of 150 to $250^{\circ}C$. The concentration of irradiated ingredients showed a greater impact on identification characteristics than their radiation doses. TL ratios ($TL_1/TL_2$) were not able to confirm the results showing evidence of irradiation through the TL glow curve shapes. Pasteurization showed a negligible effect on the key identification parameters and did not change the shape or temperature range of radiation-specific TL glow peak, but reduced TL glow curve intensity. TL glow curve shape with the maximum peak in a temperature range of $150{\sim}250^{\circ}C$ was the most useful characteristic providing information required for confirming the irradiation status.

Changes in Thermoluminescence of Mineral Separated from Irradiated Shellfish under Various Storage Conditions

  • Yi, Sang-Duk;Yang, Jae-Seung
    • Preventive Nutrition and Food Science
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    • v.6 no.1
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    • pp.23-28
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    • 2001
  • A study was carried out to establish a detection method of irradiated shellfish through thermoluminescence (TL). The TL intensity of first glow curves for irradiated bloody, freshwater, and short-neck shellfish increased from control until 5 kGy and increased slightly room 5 kGy until 10 kGy. Maximum TL temperatures of all irradiated samples tested were below 23$0^{\circ}C$, within temperature interval of 150~25$0^{\circ}C$ recommended for evaluation. Since just in control, glow curve ratios of G3 and G4 calculated from re-irradiated (1 kGy) bloody, freshwater and shortneck were over 0.5, detection in control was possible. However, as glow curve ratios after three months were below 0.5, detection by glow curve ratios after three months was impossible. Gl, which calculated from unirradiated samples, exhibited below 0.1, they were classified as unirradiated. In all samples, all the irradiated shellfish could be classified correctly as irradiated by hemaximum TL temperatures and shape of the second glow curve because those were shown in a lower temperature region than those of the first glow curve.

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