title: Application of EPR Spectroscopy to Examination of the Effect of Sterilization Process on Free Radicals in Different Herbs.
abstract: Free radicals in the original and sterilized caraway, curry, curcuma and cardamom were studied. An X-band (9.3 GHz) electron paramagnetic resonance (EPR) spectroscopy was the experimental technique. Effect of microwave power in the range of 2.2-70 mW on amplitudes, linewidths, and lineshape parameters of the EPR spectra was tested. Free radicals concentrations in the non- and sterilized herb samples were compared. The aim of this work was to determine properties and concentration of free radicals in steam sterilized caraway, curry, curcuma and cardamom. It was pointed out that free radicals (~1018spin/g) exist in both the original and sterilized herbs. Complex free radical system with oxygen and carbon paramagnetic centers characterizes the examined herbs. Homogeneously dipolar broadened EPR spectra were measured for all the tested herbs. Slow spin-lattice relaxation processes exist in the examined samples. Practical usefulness of EPR method in food technology was discussed.
authors.affiliation: Department of Food and Nutrition, Medical University of Silesia in Katowice, Jedności 8, 41-200 Sosnowiec, Poland.
authors.forename: Katarzyna
authors.initials: K
authors.lastname: Pawłowska-Góral
authors.forename: Paweł
authors.initials: P
authors.lastname: Ramos
authors.forename: Barbara
authors.initials: B
authors.lastname: Pilawa
authors.forename: Ewa
authors.initials: E
authors.lastname: Kurzeja
keywords: EPR spectroscopy; Free radicals; Herbs; Sterilization process