Novel multi-phase nano-emulsion preparation for co-loading hydrophilic arbutin and hydrophobic coumaric acid using hydrocolloids

This study was designed to co-load hydrophilic arbutin and hydrophobic coumaric acid in nano-sized multi-phase emulsion (W/O/W) using hydrocolloids and examined for its various stability and bioaccessibility parameters. The creaming stability and sensory evaluation of emulsion in Lactobacillus beverage and its release kinetics in simulated oral and gastrointestinal conditions were also studied. Results revealed that multi-phase emulsion exhibited small particle size and low polydispersity index with high zeta potential. Higher encapsulation efficiency was also observed. Moreover, the multi-phase emulsion showed good storage stability under different conditions. The multi-phase emulsion also showed controlled release of arbutin and coumaric acid in simulated conditions with increasing bioaccessibility. Stability of these compounds under unfavorable conditions was also found to be increased. Moreover, high creaming stability and sensory evaluation score of the multi-phase emulsion suggested that the formulation was capable of retaining arbutin and coumaric acid in Lactobacillus beverage without affecting its sensory properties. These results indicated that the multi-phase nanoemulsion (W/O/W) could effectively co-deliver hydrophilic arbutin and hydrophobic coumaric acid and thus could be a novel delivery method for increasing bioaccessibility of these nutraceutically important phenolic compounds.