Preparation and stability of W/O/W emulsions containing sucrose as weighting agent

The objective of present study was to evaluate the use of sucrose as a weighting agent in W/O/W emulsions. Placing sucrose in the internal water phase could increase the density of the oil droplet and provide natural weighing to the oil phase. A 60 wt% sucrose solution with or without gelatin served as inner aqueous phase (W). Orange oil terpenes (OT) or Miglyol 812 (MCT) were compared as oil phase (O). Different concentrations of polyglycerol polyricinoleate (PGPR) were evaluated as lipophilic emulsifier. Gum Arabic (GA), modified starch (MS), and/or Tween 20 were evaluated as hydrophilic emulsifiers. Mean droplet diameter (MDD) and encapsulation efficiency (EE) were measured with yellow #6 as a marker incorporated in inner aqueous phase. Nano-sized W/O emulsions were formed with MDD as small as of 72 nm by using Microfluidization. Gelling the inner phase significantly increased droplet size of W/O emulsions. GA-stabilized W/O/W emulsions showed highest dye retention (EE > 85%) and smallest MDD (0.75 to 4.5 μm), whereas MS and Tween 20 showed poor performance (EE <50%). Both concentrated and diluted W/O/W emulsions with MCT as oil phase stabilized by GA showed good stability in MDD, EE and turbidity during four weeks of storage at 23 °C. The results demonstrated the potential and challenges of creating stable beverage cloud applications based on W/O/W emulsions using sucrose as a natural weighting agent.