Dielectric Properties of Fruits and Vegetables As a Function of Temperature and Moisture Content

摘要

The relative permittivity, ε', and relative loss factor, ε", of apple, chervil, mushroom, parsley, and strawberry were measured at 2800 MHz, with a cylindrical TM_012 perturbation cavity. The measurements were made over a range of mois- tures and temperatures. The results show that the relative loss factor has a maximum value at an intermediate moisture content for all the fruits and vegetables investigated. The relative permittivity decreases with increasing temperature at a high moisture content, but at intermediate moisture contents ε' increases with temperature. Equations were developed for interpolation of the relative permittivity and the loss factor.