Impedance Measuring Technique for Identifying Irradiated Potatoes

抄録

The magnitude, resistance, and reactance of impedance of potato tubers were significantly influenced by irradiation. Although different types of electrode resulted in different values of these impedance parameters, the ratios of the impedance parameters at 5 kHz to 50 kHz got rid of the influence of the type of electrodes. The ratio of impedance magnitude at 5 kHz to 50 kHz (Z_5k/Z_50k) resulted in a larger difference between unirradiated and irradiated potatoes than those of resistance and reactance. The degree of difference in Z_5k/Z_50k between unirradiated and irradiated potatoes was dependent upon the measuring temperature and the region of the tuber punctured with electrodes. The impedance ratio (Z_5k/Z_50k) measured at 22-25°C at an apical region of potato tuber with 1 mA of alternating current resulted in the best identification of irradiated potatoes and enabled differentiation of irradiated potatoes from unirradiated ones for up to 6 months.