The Feasibility of Continuous Heat Sterilization of Food Products Using Microwave Power

摘要

A continuous system for the thermal processing of food in plastic pouches has been developed in which over-riding air pressure is used to balance internal pressure and prevent pouch rupture. The pouches are filled with 6-8 ozs of food product, heat sealed and introduced through an airlock onto a conveyor inside a 5-inch 1.D plastic(epoxy fiberglass) pipe which is located within a (Litton Model C-10S-2) microwave conveyor cavity. Microwave energy is supplied by four modular units generating a total of 19kW at 2450 MHZ. Conveyor speed and power level are regulated to provide the desired process time and temperature. Pouch cooling is accomplished either by a refrigerated platen under the final section of the conveyor or by immersion in a cold water reservoir. Pouches are over-packed after processing, in a barrier film (aluminum foil-plastic) laminate to provide protection and storage stability. Several food products including frankfurters and chicken ala king have been processed in order to evaluate the system. Design and performance data are discussed and an evaluation is made of the future potential, both from the technical and economic points of view. (Author)