Properties of whey protein isolate-dextran conjugate prepared using pulsed electric field

Effect of pulsed electric field treatment on whey protein isolate-dextran conjugation in aqueous solution via Maillard reaction was investigated. Significant changes in browning intensity, free amino group content and SDS-PAGE profile showed that whey protein isolate-dextran conjugate was successfully formed using pulsed electric field treatment. Moreover, higher pulsed electric field intensity enhanced the extent of glycosylation. Meanwhile, the secondary structure of whey protein isolate had a considerable loss due to the covalent attachment of dextran. The functional properties, such as solubility, emulsifying activity and emulsion stability were also evaluated. Compared with initial whey protein isolate, the solubility and emulsifying properties were significantly improved. At the same time, glycosylation also inhibited heat-induced aggregation after treated at 80 degrees C for 20 min. All data showed that pulsed electric field treatment could be applied as a means to prepare WPI-dextran conjugate with better functional properties. (C) 2011 Elsevier Ltd. All rights reserved.