Stable and bioactive W/O/W emulsion loaded with Pitanga (Eugenia uniflora L.) leaf hydroethanolic extract

Pitanga leaf hydroethanolic extract (PLHE) presents high antioxidant and antimicrobial activities. The encapsulation of this extract in W/O/W double emulsions could protect its bioactive properties. The objective of this research was to encapsulate PLHE in the inner W phase of a double emulsion and analyze the emulsifiers concentrations and phase ratios effects on its droplet size and the physical stability. Moreover, the double emulsion rheological behavior, antioxidant and antimicrobial activities in their more stable formulation was investigated. For comparison purpose, antioxidant and antimicrobial activities of the PLHE was also determined. Overall, the droplet size and stability were affected by the concentration of emulsifiers and phase ratios. The double emulsion presented heterogeneous droplet size, good physical stability and non-Newtonian behavior. PLHE presented high antioxidant and antimicrobial activities, which was maintained after processing to encapsulation into double emulsion. In conclusion, it was possible to produce active and stable double emulsion loaded with PLHE.

Automated summary

The study showed that the concentration of emulsifiers and phase ratios affect the droplet size and stability of the double emulsion. The double emulsion exhibited heterogeneous droplet size, good physical stability, and non-Newtonian behavior.