Dielectric Measurements of Ground Beef in Microwave Frequencies at Different Hydration Levels

Readily available animal tissue such as ground beef is a convenient material for mimicking the dielectric properties of biological tissue when validating microwave imaging and sensing hardware and techniques. The reliable use of these materials depends on the accurate characterization of their properties. Tissue water content is a dominant factor in microwave frequency tissue properties, thus the effect of dehydration must be considered. The dependence of tissue properties on hydration is also important for new applications of microwave sensing for hydration monitoring. A new protocol for measuring the dielectric properties of heterogeneous tissue and rigorously analyzing the results is presented. The effect of dehydration on the permittivity and conductivity of ground beef samples is explored. A linear mixed effect model was employed to examine the impact of the frequency-dependent behaviour of the dielectric properties. As expected, dehydration impacts both the permittivity and conductivity of ground beef samples with a larger influence on permittivity.