The process, which combines pressure cooking with microwave techniques, has been developed by Professor Juming Tang of the Department of Biological Systems Engineering at Washington State University.
While conventional retorting and sterilisation processes take up to an hour and often under pressure, the process developed by Prof Tang takes about four minutes.
Prof Tang has been working on high-quality military meal-to-eat rations that could be used for the retail markets. He has also been working on the world’s first pilot-scale 27 Mhz RF sterilisation units for large institutional food trays. With this process the processing time for six-pound trays was reduce to 20 minutes from between two and two-and-a-half hours with conventional techniques.
How the process could be used for metal packaging is not clear. Unless the container is shallow, in which case the microwave heating is more evenly distributed, the food is shielded and hot heated homogeniously."