Dielectric properties of dried turmeric rhizomes and related storage insects

The dielectric properties of dried turmeric finger rhizomes and the related storage insects namely Stegobium paniceum L. (drugstore beetle) and Lasioderma serricorne F. (cigarette beetle), were studied using an impedance analyzer. The measurements were conducted with the frequency range of 25 to 32 MHz and at temperatures ranging from 60 to 80°C. The dielectric constant and loss factor decreased with increasing frequency from 25 to 32 MHz at all temperatures whereas, the dielectric constant and loss factor increases with increasing temperatures at constant frequency for all samples were studied. The sample with maximum moisture content revealed maximum dielectric property. New equations were formulated through regression analysis to explore how the dielectric properties are influenced by changes in temperature and frequency.