Developments in Radio Frequency Pasteurization of Food Powders

Radio frequency (RF) heating has been used in several industries and has a great potential to be used as an alternative pasteurization technology in the food industry. Efforts have been undertaken to develop uniform heating throughout the food to ensure product safety and extend its shelf life. Among the food products, food powder is a large category of low moisture foods and generally considered as microbiologically safe due to their low water activity. However, recent outbreaks indicate that certain microbial species can survive for a significant time period in contaminated low moisture foods. For this reason, the development of effective pasteurization techniques for low moisture foods has become more of an issue. This review focuses on the literature on RF heating for pasteurization of food powders. In addition to a brief introduction to food powders and RF heating applications, the factors affecting heating uniformity, dielectric properties of various food powders found in the literature and microbial validation studies are covered.