Identification of irradiated Turkish foodstuffs combining various physical detection methods

Different kinds of Turkish export foodstuffs such as spices, tea, dried fruits and nuts have been investigated whether a possible radiation treatment could be identified using various methods which have been adopted or proposed as EN Standards. Samples were irradiated at doses of 0.5, 1, 3, 5, 10 kGy by 10 MeV electrons. The foodstuffs were at first analysed applying Photostimulated Luminescence (PSL) as a rapid screening method. As a second rapid method, Electron Spin Resonance (ESR) spectroscopy has been applied. Finally, Thermoluminescence (TL) analysis was applied if silicate minerals could be isolated in an adequate amount from the foodstuffs. A successful application of the rapid methods was dependent on the nature of samples and processing conditions. Weak signals of some samples caused problems in detection. Therefore, an alternative method such as TL, although being much more cumbersome and more time-consuming, was applied for a definite proof of radiation treatment. A combination of the applied methods was considered successful to obtain reliable results.