THERMOLUMINESCENCE SPECTRA OF INORGANIC DUST FROM IRRADIATED HERBS AND SPICES

Thermoluminescence (TL) is used to determine whether certain foodstuff s have been irradiated. A high sensitivity TL spectrometer was used to analyze irradiated and unirradiated inorganic dusts from herbs and sp ices. Unlike earlier TL work using emissions in the UV-green spectral range, the spectrometer monitored transient TL emissions across the sp ectral range from UV to infra-red as samples were heated to 400 degree s C. A strong high temperature red emission peak was detected in all i rradiated samples. This signal was much higher than the background lev el, insensitive to post-irradiation light exposure, and has potential for irradiation exposure determination.