Effect of high-voltage electrostatic field pretreatment on the antioxidant system in stored green mature tomatoes

Abstract

High-voltage electrostatic field (HVEF), as a feasible and non-chemical technique, applied to food preservation is a new area of study. Our previous research suggested HVEF could maintain the quality of tomato in storage. The present article intensively investigated the effect of HVEF pretreatment on antioxidant system of green mature tomato in storage. Green mature tomatoes were exposed to negative (or positive) HVEF for 2 h at 20 °C and then stored for 24 days at 13 ± 1 °C, 85-90% relative humidity. The results indicated HVEF significantly reduced contents of O(2)(-) and H(2)O(2) of tomato fruits during storage compared to the control. HVEF treatment also enhanced the activities of antioxidant enzymes including catalase, superoxide dismutase, ascorbate peroxidase and peroxidase. The contents of non-enzyme antioxidant components including reduced glutathione, phenols and ascorbic acid also were increased by HVEF treatment. However, HVEF treatment did not increase the content of lycopene in tomato fruit. HVEF treatment could promote the antioxidant capacity of tomato fruits in storage. Further research is be highly recommended to understand the mechanisms improving the antioxidant capacity of tomato fruits by HVEF.