Encapsulation properties, release behavior and physicochemical characteristics of water-in-oil-in-water (W/O/W) emulsion stabilized with pectin-pea protein isolate conjugate and Tween 80

Water-in-oil-in-water (W-1/O/W-2) double emulsion is one of the most efficient drug delivery systems. In the double emulsion, the release of a target compound from one phase to another can be controlled by the emulsion composition, emulsification and preparation condition. Tween 80 is mainly used as a high HLB emulsifier; while it may cause many side effects on the human health. The main goal of the present study was to investigate the efficiency of a new hybrid polymer (pectin-pea protein isolate conjugate) as a potential alternative for Tween 80. In this study, the efficiency of different types and concentrations of hydrophilic emulsifier (i.e. Tween 80, native pectin and pectin-PPI conjugate) and hydrophobic emulsifier (i.e. PGPR) on the release behavior of Tartrazine as a marker and other characteristics of W-1/O/W-2 double emulsion were investigated. The double emulsion containing 2% pectin-PPI conjugate and 2% PGPR had proper encapsulation stability (37.05%). Conversely, the sample stabilized with Tween 80 (2%) and PGPR (either 2% or 5%) had relatively poor encapsulation stability after one-month storage (8.97% and 6.35%, respectively). In most cases, the double emulsion stabilized with pectin-PPI conjugate provided stronger encapsulation properties, smaller droplets, and higher zeta potential than other emulsions containing the native pectin and Tween 80. The current study reveals that the pectin-PPI conjugate (3: 1) can be used a proper replacer for Tween 80 in stabilizing the double emulsion. The application of pectin-PPI conjugate in the double emulsion led to reduce the percentage of PGPR in the formulation, providing safer product. (C) 2016 Elsevier Ltd. All rights reserved.