Dielectric Properties and Heating Rates of Frozen Chicken Breast During Thawing: A Comparison Between Radio Frequency and Microwave Treatments

To support the development and computer simulation of radio frequency (RF) and microwave (MW) thawing processes, this study characterized the dielectric properties and penetration depth of chicken breast across a frequency range of 10–3000 MHz and temperatures from −20 °C to 10 °C. The influence of three RF anode voltages and four MW power levels on heating rates was also evaluated. Results showed that both the dielectric constant and loss factor decreased with increasing frequency, with the most significant reduction occurring between 10 and 60 MHz. In contrast, these properties increased with temperature, exhibiting a sharp rise during the phase transition zone (−5 to 0 °C). Penetration depth decreased with frequency and was consistently higher under RF than MW exposure. High-precision regression models (R2 > 0.97) were established to describe these relationships. RF heating achieved more uniform temperature distribution compared to MW, which showed pronounced center-corner temperature differences. By integrating experimental measurements with mathematical modeling, this work provides key insights and reliable data for optimizing RF and MW thawing strategies in industrial applications.