Applications of electricity and specifically pulsed electric fields in food processing: Historical backgrounds

- Early studies on impact of electricity on growth, vegetation and germination are presented.
- The first applications of pulsed electric fields (PEF) in food processing are reviewed.
- The period before 1990th is covered.

Starting from two-three decades ago pulsed the electric field (PEF) treatment became very popular in a food industry. Many important effects and mechanisms related with impact of PEF on bio-, food or agricultural products have been discovered and elucidated for this period. Concept of electroporation has been fundamentally developed. The positive effects of PEE-assisted processing for inactivation of microorganisms, extraction, pressing, osmotic dehydration, drying, and freezing have been observed. Recent development and success of PEF applications has been also supported by the growing number of commercially available PEF generators with different characteristics, power and particular protocols. In the current paper, research works and applications of electricity and specifically pulsed electric fields in food processing over the period until the middle of the 1990s are summarized. A historical overview is presented in two steps devoted to: (a) the early studies on impact of electricity on growth, vegetation and germination and treatment of food by electricity before the 1940s and (b) the development of concept of selective electroplasmolysis and the first attempts to use the electricity and specifically the PEF treatment in food industry in the period between the 1940s ;and 1990s.Industrial relevanceDuring the long history of testing of electricity and specifically the PEF treatment in industrial relevant processing the serious problems and obstacles were revealed. Many pilot scale constructions were proposed and tested during the period between the 1940s and until the middle of the 1990s by different investigators from West Germany and USSR (Ukraine and Moldova). However, finally that technology was not industrialised due to the technical difficulties, the absence of necessary financial support and the lack of knowledge about basic mechanisms responsible for the impact of PEF. This historical experience can be very instructive for the development of modern applications of PEF technology in food industry.