title: A new approach for extension of the identification period of irradiated cellulose-containing foodstuffs by EPR spectroscopy.
abstract: We report on the possibility of identification by EPR spectroscopy of some irradiated cellulose-containing foodstuffs, at a relatively long time after the irradiation, when the characteristic EPR spectral lines of the cellulose free radical have essentially disappeared. In such cases rather expensive and time-consuming methods (e.g. thermoluminescence analysis) have to be applied. The present communication demonstrates with some pre-irradiated spices, dried medicinal and sweet herbs that simply heating the samples to 60 degrees C for one hour leads to a significant (50% or more) decrease of the EPR intensity of the remaining central line of the samples. For comparison, the loss in the intensity of the same line upon heating non-irradiated samples at 60 degrees C for one hour was only about 10%. This inexpensive new procedure will extend the post-irradiation period in which EPR can be used for distinguishing irradiated from non-irradiated samples, of certain cellulose-containing foodstuffs.
authors.affiliation: Institute of Catalysis, Bulgarian Academy of Sciences, Sofia, Bulgaria. ndyepr@bas.bg
authors.forename: N D
authors.initials: ND
authors.lastname: Yordanov
authors.forename: V
authors.initials: V
authors.lastname: Gancheva
mesh_terms: D002482:Cellulose / Q000032:analysis*; D004578:Electron Spin Resonance Spectroscopy / Q000379:methods; D005504:Food Analysis / Q000379:methods*; D005514:Food Irradiation; D006358:Hot Temperature; D019684:Magnoliopsida; D010946:Plants, Medicinal; D017365:Spices
chemical_list: D002482:Cellulose