title: Luminescence characteristics for identifying irradiated black soybeans.
abstract: OBJECTIVE
  Considering the commercial use of food irradiation and the prevalence of international trade of irradiated food and agricultural commodities, black soybeans originating from China or Korea were irradiated at 0-5 kGy. Photostimulated luminescence (PSL) and thermoluminescence (TL) were investigated for their ability to identify characteristics that would distinguish irradiated from non-irradiated samples.
  
  
  METHODS
  Dried black soybeans [Glycine max (L.) Merr.] were irradiated using a Co-60 gamma irradiator or an electron-beam accelerator and then analysed by PSL and TL.
  
  
  RESULTS
  PSL photon counts were higher in irradiated samples than in non-irradiated ones and increased with applied doses, making it possible to distinguish irradiated from non-irradiated samples. The TL analysis revealed glow curves (TL₁) with low intensity for non-irradiated samples but a higher intensity (approximately 200°C) for irradiated samples, showing increased intensities with radiation dose. The minerals were re-irradiated at 1 kGy and the second TL glow curve (TL₂) was measured. Based on the calculated TL ratios (TL₁/TL₂) and the shape of TL₁ glow curves, the irradiated samples could be distinguished from non-irradiated ones.
  
  
  CONCLUSIONS
  PSL and TL are effective screening and reference methods for distinguishing gamma ray or electron beam irradiated black soybeans from non-irradiated black soybeans.
authors.affiliation: Department of Food Science and Technology, Kyungpook National University, Daegu, Republic of Korea.
authors.forename: Qiong-Wen
authors.initials: QW
authors.lastname: Jin
authors.forename: Jae-Jun
authors.initials: JJ
authors.lastname: Ahn
authors.forename: Gui-Ran
authors.initials: GR
authors.lastname: Kim
authors.forename: Dong-Gil
authors.initials: DG
authors.lastname: Kim
authors.forename: Joong-Ho
authors.initials: JH
authors.lastname: Kwon
mesh_terms: D003132:Commerce; D005720:Gamma Rays; D049449:Luminescence; D008163:Luminescent Measurements; D013025:Glycine max / Q000528:radiation effects*; D013696:Temperature