Electrochemical reaction and oxidation of lecithin under pulsed electric fields (PEF) processing

Pulsed electric fields (PEF) processing is a promising nonthermal food preservation technology, which is ongoing from laboratory and pilot plant scale levels to the industrial level. Currently, greater attention has been paid to side effects occurring during PEF treatment and the influences on food qualities and food components. The present study investigated the electrochemical reaction and oxidation of lecithin under PEF processing. Results showed that electrochemical reaction of NaCl solutions at different pH values occurred during PEF processing. Active chlorine, reactive oxygen, and free radicals were detected, which were related to the PEF parameters and pH values of the solution. Lecithin extracted from yolk was further selected to investigate the oxidation of food lipids under PEF processing, confirming the occurrence of oxidation of lecithin under PEF treatment. The oxidative agents induced by PEF might be responsible for the oxidation of extracted yolk lecithin. Moreover, this study found that vitamin C as a natural antioxidant could effectively quench free radicals and inhibit the oxidation of lipid in NaCl and lecithin solutions as model systems under PEF processing, representing a way to minimize the impact of PEF treatment on food qualities.