Detection of irradiated foods by the thermoluminescence

Our study demonstrated that the effects of the several temperature ranges for integrating TL glow intensity on the TL glow ratios by using spice-set purchased at a Turkish air port. The spice set had no labeling of irradiation foods, but nine of 12 spices were judged as irradiated food in this study. Those temperature ranges were defined by evaluating the glow curves of irradiated TLD-100 chip (167-230°C), TLD-100 disc (177-238°C) and Dolomite element (145-258°C). Those are relatively stable and the difference of typical glow peak temperatures of TLD-100 disc in two institutes was less than 2%. On the other hand, Those of TLD-100 tip was shift to higher temperature side at about 4°C because of declining of thermal conductance. The temperature ranges defined by TLD-100 were showed that discriminate more clearly between irradiated and nonirradiated spices compared with the full temperature range of TL measurement (70-400°C). With the exception of low glow intensity, background measurement for estimating net glow intensity was not necessary because TL glow ratio was hardly influenced whether the background measured or not.