Design of a PEF treatment device for experiments on food preparation

The treatment of food by pulsed electric fields (PEF) is currently investigated as an energy-efficient alternative for the preparation of meals instead of cooking. It is the idea to open the cells by charging their membranes causing irreversible permeabilization rather than thermal denaturation. For such investigations a PEF-treatment device has been designed. It comprises a test vessel for the preparation of food, a Marx generator equipped with semiconductor switches as pulse generator, a power supply, and control circuitry. The pulse circuit has been designed as RLC circuit. It generates pulses with a pulse length in the microsecond range up to a voltage of 20 kV across the load. The impedance at the electrode system inside the test vessel has been matched such, that the pulse shape is nearly critically damped. The paper describes the design of the pulse circuit and the semiconductor switch, and highlights some aspects of the design of the PEF treatment device.