Identification of irradiation treatment of spices by thermoluminescence ofcontaminating minerals

Five spices, cumin, coriander, clove, cinnamon and black pepper were irradi ated by gamma-ray doses of 1.0 and 5.0 kGy and thermoluminescence (TL) meth od was used for identification of the irradiation treatment. The TL respons e of the minerals isolated from irradiated samples was much higher as compa red to the mineral particles from unirradiated control samples. For the nor malisation of results the separated minerals were re-irradiated to a normal isation dose of 1.0 kGy and the TL glow curve was recorded a second:time. B y comparing the glow curves of irradiated and unirradiated samples, finding the ratio of the areas of first and second glow curves (TL1/TL2) and compa ring the shapes of the glow curves, all the irradiated and unirradiated sam ples were identified correctly.