Simultaneous encapsulation of trans-resveratrol and vitamin D-3 in highly concentrated double emulsions

BACKGROUND Encapsulation of biocompounds is essential to protect them from environmental factors that could enhance their oxidation or cause them to lose their beneficial properties due to extreme photosensitivity, among other factors. The main goal of this work was to study the feasibility of preparing concentrated double emulsions with a high loading capacity containing simultaneously trans-resveratrol (RSV) and vitamin D-3 (VitD(3)). Such emulsions could be used for food fortification or pharmaceutical formulations or as vehicles for targeted controlled release. RESULTS In order to achieve large concentrations of the encapsulated compounds, all the double emulsions were formulated using a W-1/O in W-2 ratio of 80/20, while the ratios tested for W-1 in O where 20/80 and 30/70. All the emulsions were characterized by droplet size, morphology, colloidal stability and encapsulation efficiency (EE) over a period of 6 weeks. VitD(3) and RSV concentration were determined by a technique based on reverse-phase high-performance liquid chromatography. The viability of preparing concentrated W-1/O/W-2 emulsions containing both biocompounds has been demonstrated with satisfactory results. Initial RSV concentrations in the concentrated double emulsions formulated varied from 5.0 to 8.3 mg L-1, while for VitD(3) values of 28-32 mg L-1 were obtained. The presence of VitD(3) retarded RSV release in the formulated emulsions. It was observed that after 1 week of storage RSV EE increased around 10-50% when VitD(3) was simultaneously encapsulated. CONCLUSION Simultaneous encapsulation of RSV and VitD(3) was possible in high internal phase emulsions. The emulsions presented high colloidal stability, being suitable for food fortification applications. (c) 2020 Society of Chemical Industry