Determination of dielectric properties of corn seeds from 1 to 100 MHz

The dielectric properties of corn seeds were determined in the ranges of 9.71–21.51% wet basis (w.b.) for moisture content, 772.5–902.2 kg/m3 for bulk density and 1–100 MHz for frequency of applied electric field using a coaxial capacitor sample holder. Effects of the parameters such as moisture content, bulk density and frequency on the dielectric properties were investigated. The dielectric constant, loss factor and loss tangent were greatly affected by the moisture content, frequency and bulk density. The moisture content was the most significant factor affecting the dielectric properties of corn seeds. The dielectric constant, loss factor and loss tangent increased with increasing moisture content and bulk density. The second and third-order polynomial equations were proposed to describe the existing relationship between dielectric properties and moisture content. Dielectric measurements provided new information concerning moisture content and bulk density dependent behaviour of dielectric properties of corn seeds that may be useful in sensing of the moisture content.

Graphical AbstractEffects of the moisture content, bulk density and frequency on the dielectric properties of corn seeds were presented. The moisture content was the most significant factor affecting the dielectric properties of corn seeds. The second and third degree polynomial equations were found to be accurate enough for predicting the dielectric constant and loss factor of corn seeds.Figure optionsDownload full-size imageDownload as PowerPoint slide