Effects of electrostatic field-assisted freezing on the functional properties and aggregation behavior of gluten

Abstract

Changes in gluten during the freezing process could cause a deterioration in dough quality, which would be solved by electrostatic field treatment. This paper investigated the effects of electrostatic field assisted freezing (EFAF) on the functional properties, structural characteristics and aggregation behavior of gluten. The results showed that EFAF improved the functional properties of gluten with enhanced water holding, emulsifying and foaming properties. When the electrostatic field was applied, the α-helix content and g-g-g conformation of gluten proteins increased with a maximum of 27.50 % and 40.05 %, respectively, which were significantly different from the control (P < 0.05). The degree of depolymerization of gluten macromolecules decreased when the electrostatic field was applied, and was obtained to be the lowest at 600 V with 5.71 %, which was significantly different from that without applied electrostatic field (P < 0.05). After EFAF, AFM analysis showed a more intact glutenin chain structure and smaller particle size of the gliadin. These results indicated that EFAF improved the functional properties of gluten proteins by the mechanism of slowing down the depolymerization of gluten macromolecules, maintaining the chain structure of gluten, stabilizing the intramolecular disulfide bonds of gliadin, and stabilizing the microstructure of gluten.