Continuous flow processing of foods using cylindrical applicator microwave systems operating at 915 MHz

Microwave heating of foods is a proven and mature technology for household applications. However, industrial applications of microwave heating of food and biomaterials are scarce, due to the lack of suitable equipment and research on the subject. Aseptic processing and packaging of foods offers products of high quality with long shelf life. Aseptic processing of low thermal diffusivity and high viscosity food and bio products can lead to diminishing the quality of such products due to long exposures to high temperatures.;Industrial Microwave Systems (Morrisville, NC) invented a system that allows continuous flow microwave heating of foods in industrial scale, by focusing the microwave energy in a specially designed cavity. Food products can be pumped through a microwave transparent tube located in the focused area of the cavity and be heated with short time exposure to the microwave energy. Cooperation between Industrial Microwave System and North Carolina State University started this research.;This research evaluated the feasibility to use IMS microwave focused cylindrical applicators, operating at 915 MHz, for continuous flow aseptic processing of fluid food materials. In order to evaluate the feasibility of using continuous flow microwave heating system to process food products, a protocol to determine this feasibility was devised. Among other findings in this study the following are noteworthy; a method to determine the temperature profile within a cross sectional area of the tube; a method to predict feasibility of a product to be processed by measuring its dielectric properties; and testing sequence to scale-up from bench-top to industrial scale operation were defined.;The findings of this work, and the methodologies developed can be of use to designers and processors alike to expand the use of this technology in the food an bio process industries.