Encapsulation of yacon (Smallanthus sonchifolius) leaf extract by supercritical fluid extraction of emulsions

Extracts with biological activities need to be preserved, as they can be degraded if exposed to light or heat. This work reports results of microparticles formation of yacon leaf extract with modified maize starch as encapsulated agent using Supercritical Fluid Extraction of Emulsions (SFEE). The variable investigated were pressure (9-13 MPa) and emulsion flow rate (Q(E)) (0.5-1.5 mL/min) on the encapsulation efficiency (EE) and residual ethyl acetate content. The highest EE was 68.2 %, performed at 9 MPa and Q(E) of 1.5 mL/min. The obtained particles were spherical, with size ranging from 92 to 450 nm. Analyses showed that: (i) the particles presented an amorphous characteristic; (ii) there was no degradation of the extract during the encapsulation; (iii) the SFEE improved the preservation of the antioxidant activity of the samples. This study shows the potential of using a new technology for particle production. (C) 2020 Elsevier B.V. All rights reserved.