Improving radio-frequency heating uniformity to ensure food safety

Radio frequency (RF) heating is a promising technology for pasteurization and disinfestation of foods and agricultural products processing, while heating non-uniformity remains a critical barrier to industrial application. This review summarised advances in RF-material (dielectric properties) interactions, reviewed industrial and laboratory applications, compared quantitative heating uniformity metrics and analysed the joint effect of RF equipment design and sample-specific dielectric properties on temperature non-uniformity. A three-step optimization framework is proposed: (1) characterizing the product properties, (2) matching or designing the appropriate RF system, auxiliary mixing/rotation and dielectric or metallic materials, and (3) quantifying and iteratively optimizing heating uniformity through experiments or computer simulations. Current advances rely mainly on dynamic mixing/rotation (to exchange hot and cold regions) and electromagnetic field shaping (via electrode redesign and dielectric/metallic coupling), with multiphysics modeling and dielectric-guided design markedly enhancing performance. However, generalizable process selection models and affordable continuous equipment for large-scale application are still lacking. Moreover, integrating real-time sensing, artificial intelligence-driven optimization, and modular hardware is essential for delivering low-carbon, energy-efficient RF processing at industrial scale.