The PLC system controls the whole process of heating, warm keeping, cooling. The temperature and pressure in the kettle are preestablished according to the curve. The calefactive and cooling are divided into many sections. This technology can reduce the temperature distance between the food surface and the food center. There are 8sections in calefactive process. All the parameters can easily input by PLC touching screen, you can also storage 10 sets sterilize parameters in advance, during the change of the material, just selected the parameters is fine.