Effect of Pulsed Electric Fields on Food Constituents

Abstract

The use of pulsed electric fields (PEF) for food preservation has been increasingly studied in the recent decades by many research groups. This technology has been proven as a good alternative to conventional heat treatments as it better preserves the nutritional and organoleptic characteristics of the products. For instance, several studies have assessed the impact of PEF processing on different nutritional compounds and the quality of the final product. The main molecules that have retained the attention of food scientists and industries are proteins and free amino acids, lipids and free fatty acids, vitamins, and polyphenols. PEF processing of food products demonstrated changes in the structural conformation of proteins and increased amounts of free amino acids. Some research works have reported minor changes in the total fat and either increased or decreased amounts of free fatty acids. Vitamins showed also some modifications and conversions of carotenoid molecules into others. Regarding total phenolic compounds, it was demonstrated that they are resistant to the effects of PEF. The use of PEF processing may thus involve, in addition to the preservation of food products, some changes in the nutritional attributes, which represent an important challenge to replace heat processing in food industries. Some examples that demonstrate the impact of electrical pulses on the different food constituents (macro- and micronutrients as well as bioactive compounds) are shown in this chapter.