DIELECTRIC PROPERTIES OF IN-SHELL AND SHELLED PEANUTS AT MICROWAVE FREQUENCIES

摘要

Dielectric properties (ε'ε" ) of ground samples of in-shell and shelled peanuts (Arachis hypogaea L.) were measured for several densities, temperatures, and moisture contents in the range of 300 to 3000 MHz- Dielectric mixture equations were used to correlate the dielectric properties with density. The coefficients of quadratic and linear dielectric mixture equations are tabulated for 915 and 2450 MHz, for different temperatures and moisture contents. The values of the dielectric constant (ε') and loss factor (ε") of bulk in-shell and shelled peanuts were determined by extrapolation of the first-and second-order polynomials that relate ε' and ε" with density. An equation that determines the dielectric properties of "nominal" peanut pods (in-shell peanuts) and kernels (shelled peanuts) as a function of their temperature and moisture content was determined by using multiple linear regression.