Detection of Irradiated Model Food Containing Salt by Thermoluminescence Measurement

Model food containing common salt(NaCl) was subjected to the thermoluminescene(TL) detection whether it is irradiated or not. Salt irradiated with $^60Co$-gamma ray and electron beam exhibited a characteristic TL gowcurve depending on the irradiation dose, showing major peaks at $206^{\circ}C$ and $326^{\circ}C$. The intensity of TL glowcurves was directly proportional to the irradiated doses regardless of irradiation sources at each concentration of salt. A high correlation coefficient was observed for irradiated salt between the irradiation doses and the corresponding TL responses. At the same dose, the intensity of TL glowcurve increased as the concentration of salt increased in the test sample. TL glowcurves of nonirradiated salt and irradiated model food without salt were negligible and similar to a baseline . However, irradiated model food containing salt gave rise to a characteristic TL glowcurve with two major peaks at about $240^{\circ}C$ and $300^{\circ}C$, respectively. The results showed that salt played a role as an internla as well as external indicator in TL measurements, indicating that TL will be applicable to other condiments and spices with salt for their detection whether they are irradiated or not.