Production of copaiba (Copaifera officinalis) oleoresin particles by supercritical fluid extraction of emulsions

Abstract

Suspended particles of copaiba (Copaifera officinalis) oleoresin were produced by supercritical fluid extraction of emulsions (SFEE), using modified starch Hi-Cap 100® as core material. First, ultrasound was applied to produce oil in water (O/W) emulsions with droplet diameter of 261.7 ± 2.2 nm. In SFEE, CO2 and emulsion flow rates, and solvent extraction time were evaluated in terms of residual ethyl acetate content (REA) and β-caryophyllene recovery in the suspension. SFEE achieved 94.1% reduction of ethyl acetate and β-caryophyllene recovery of 7.3%. This REA is within the exposure limit of ethyl acetate (5000 ppm per day). The suspended nanoparticles’ size showed little variation from the emulsion droplet diameter. Finally, the suspensions were dried to obtain powder particles. Field emission scanning electron microscopy (FESEM) revealed different structures depending on the drying method (freeze-drying or spray-drying). Moreover, confocal laser scanning microscopy (CLSM) confirmed that copaiba oleoresin was encapsulated in the particles.