Impact of polysaccharide mixtures on the formation, stability and EGCG loading of water-in-oil high internal phase emulsions

Water-in-oil (W/O) high internal phase emulsions (HIPEs) were prepared using polyglycerol polyricinoleate (PGPR) and polysaccharide blends consisting of konjac glucomannan (KGM) and octenyl succinic anhydride starch (OSA-starch). The formation, stability, and functionality of these emulsions were varied by adjusting the ratio of KGM and OSA-starch. Interfacial tension measurements indicated that the OSA-starch co-adsorbed to the water-oil interface with PGPR, which would have led to the formation of a polysaccharide-layer that helped prevent separation of the HIPEs. The centrifugal stability, rheological and microstructural results indicated that the W/O HIPEs exhibited well pH, ionic and thermal stability. The encapsulation efficiency, stability, and bioaccessibility of the EGCG in the W/O HIPEs were evaluated by using EGCG as a model hydrophilic nutraceutical. This study provides useful insights into the utilization of emulsion technology to reduce the fat content and improve the nutritional profile of foods with oily continuous phases, such as spreads.