Toward Uniform Microwave Heating in Food Drying: Principles, Technologies, and Emerging Trends

This is the authors' abstract. We don't add key points for this paper.

Microwave (MW) heating has transformed food processing due to its rapid, volumetric, and energy-efficient capabilities. However, achieving uniform heating remains a major challenge, often resulting in quality inconsistencies and safety concerns. This review explores the fundamental principles of MW heating and the intrinsic causes of non-uniform heating in food materials. Key influencing factors include dielectric properties, food composition, sample geometry, and dryer design. We examine current strategies to improve heating uniformity, such as modifications to MW oven design, incorporation of stirring mechanisms, and the development of hybrid heating methods. While these approaches show promise, their scalability is hindered by high costs, technological constraints, and variability in food properties. The review also highlights future directions, emphasizing the importance of advanced modelling, real-time monitoring, and innovative material engineering to enhance uniformity. By addressing these challenges, the food industry can improve product quality, safety, and energy efficiency in MW drying processes.