Encapsulation and release of vitamin C in double W/O/W emulsions followed by complex coacervation in gelatin-sodium caseinate system

Abstract

The objective of this study was to produce and characterize microcapsules for simultaneous encapsulation hydrophilic and lipophilic active substances. For this purpose, double emulsification process was employed, followed by complex coacervation in the system of two oppositely charged biopolymers, gelatin and sodium caseinate (NaCAS). Properties of the microcapsules wall have been regulated by cross-linking of the gelatin/NaCAS complex at the interface with genipin. Vitamins C and E were selected as model hydrophilic and lipophilic bioactive compounds for this study. Investigations of surface morphology, encapsulation efficiency (EE) and kinetic of vitamin C release have shown that genipin concentration as well as interaction in gelatin/NaCAS system make an influence on microcapsules properties. Genipin concentration of 2 mmol/g, was chosen as the optimal and the highest EE of the vitamins were obtained at proteins mass ratio of 2:1. The results of release kinetic determination of the vitamins showed that release mechanism is simple diffusion.