A PEF processing system consists of a high-voltage power source, an energy storage capacitor bank, a charging current limiting resistor, a switch to discharge energy from the capacitor across the food and a treatment chamber (see Figure 18.104.22.168). An oscilloscope is used to observe the pulse waveform. The power source, a high voltage DC generator, converts voltage from a utility line (110 V) into high voltage AC, then rectifies to a high voltage DC. Energy from the power source is stored in the capacitor and is discharged through the treatment chamber to generate an electric field in the food material (Eissa, 2012).
The use of electromagnetic waves to generate heat in the fruit industry can be suitable for the pasteurization of fruit preparation containing soft fruit pieces (such as strawberries, raspberries, and blackberries) and for nonchemical disinfestation system of fruits and vegetables as an alternative to methyl bromide and other chemical-based postharvest treatments, as well as commonly used quarantine methods such as cold storage and controlled atmosphere methods, in order to devitalize insects at all life cycles (eggs, larvae, pupae).