ESR: A Sensitive Technique to Irradiation Treatment of Dry Fruits

Abstract

Food irradiation is a preservation technique reported as "cold sterilization", since it has antimicrobial effects without heat increase. Standardization of detection methods for irradiated foods is important for consumer's satisfaction and for the regulatory control purpose. In the present study, electron spin resonance spectroscopy is used to detect irradiated linseeds, chickpea, black eye beans and red beans. This technique successfully identified all the irradiated samples even treated at low doses. It was found that a sharp symmetrical ESR signal at g = 2.0201 typical for free radicals appeared in case of irradiated commodities. In linseeds, chickpea, black eye beans and red beans, cellulosic radicals are produced which act as paramagnetic centers. The intensity of this ESR signal increased with the absorbed radiation dose in all the food commodities. The results of this study showed that irradiation identification by ESR is authentic and reliable.