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This paper discusses the determination of kinetic parameters for the thermal death kinetics of rusty grain beetle in stored wheat using the temperature history of wheat during 50-Ω RF heating. At 353 K, a 100% insect mortality rate was achieved at all three moisture content levels tested. At 343 K, a 100% insect mortality rate was achieved at the 15% and 18% moisture contents. Increases in the target temperature and moisture content of the wheat samples significantly increased the mortality rate of the insect pests. The thermal death kinetics of the rusty grain beetle during 50-Ω RF heating followed a 1st order reaction. The value of Ea was 97.490 J/mol, and the value of k0 was 6.74 × 1013 1/s. There was good agreement between the experimental mortalities and the simulated mortalities based on the thermal kinetic model.

Adult Tribolium castaneum infesting canola seeds at 9% moisture content were treated using a 50-Ω radio frequency heating system and the thermal mortalities of the insects were determined. The infested seeds were treated at temperatures of 24–65 °C with radiofrequency (RF) heating power at 3 kW, 5 kW, and 7 kW. More than 80% of the insects were killed at 65 °C at all the three power levels. The survival rate of the adult T. castaneum decreased with temperature and RF power level. The effect of selective heating on mortality of insects increased at the higher RF powers. An inverse simulation was used to estimate the kinetic parameters of thermal death in adult T. castaneum. The thermal kinetic models developed in this study were solved using the 4th order Runge-Kutta method on a MATLAB platform. The thermal death kinetics for adult T. castaneum followed the 1st order reaction with Ea of 97.50 kJ/mol and k0 of 6.5 × 1013. The lethal time (LTs) calculated using the thermal death kinetic model developed in the study agreed well with the LTs determined experimentally.