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The aim of this work was to verify the applicability of the European Standard EN 13751, based on Photo-Stimulated Luminescence (PSL) and the European Standard EN 1788, based on Thermoluminescence (TL), for the detection of irradiation in plant food supplement (PFS) ingredients, nuts and fresh fruits with health benefits. In particular, in this work, herbal ingredients (Camellia sinensis , Ginkgo biloba , Glycine max , Silybum marianum , Vaccinium myrtillus), almonds, hazelnuts, peanuts, pistachios, walnuts and fresh blueberries, papaya and mango, were analyzed by both stimulated luminescence methods. To verify the reliability of the methods in detecting the treatment over time, the analyses were replicated after irradiation within the product shelf life. The PSL screening method allowed to correctly identify blueberries, nuts and raw materials of PFS but failed with dried herbal extracts, mango and papaya, due to their low content of silicates. To validate the procedure elaborated during the preliminary study, blind tests, involving several national laboratories of the official control, were organized. The tests confirmed the limits in detecting dried extracts, mango and papaya by PSL technique. TL method resulted suitable as a confirmatory method for all the matrices of the study. • PSL based method came out suitable for nuts and PFS raw materials. • Dried extracts and fresh mango and papaya came out as critical matrices for PSL. • TL method is suitable for PFS ingredients, nuts, blueberries, mango and papaya. • Fading of the signal was observed but even so it was possible to detect the samples. [ABSTRACT FROM AUTHOR]

Abstract: Photo-stimulated luminescence (PSL) and thermoluminescence (TL) analyses were done to screen or identify irradiation treatment of ostrich, duck, hen and quail eggs. These eggs were gamma-irradiated at 0, 1, 2 and 3 kGy and the eggshells were used for PSL and TL analyses in a powdered form. The PSL results showed that all the non-irradiated control samples had photon counts (PCs) less than the lower threshold value (700counts/60s). Some of the irradiated samples like ostrich and duck, however, showed PCs higher than the upper threshold value (5000counts/60s), and the other irradiated samples were between the lower and upper values (700–5000counts/60s). Photon (PCs) less than the lower threshold value (700 counts/60s). Although the TL glow curves which originated from the calcite mineral present in eggshells, which were confirmed by X-ray diffraction spectroscopy. The intensities of the first glow curves (TL1) obtained from the egg shells were less intense as compared to that of quartz or feldspar that are usually present on the surface of the food as contaminants. The intensity and shape of the first glow curve (TL1) as well as the glow curve ratios (TL1/TL2) based on a normalization step, enabled discrimination between the control and irradiated eggshells by using natural bio-inorganic minerals. [Copyright &y& Elsevier]