Avocado Oil Incorporated in Ultrafine Zein Fibers by Electrospinning

The objective of this study was to encapsulate avocado oil in ultrafine zein fibers by the electrospinning technique. Avocado oil, at concentrations of 15 and 30% ( w/w ), was incorporated into 20, 25 and 30% ( w/v ) zein polymer solutions. The polymer solutions were evaluated for viscosity and electrical conductivity. The zein fibers containing the avocado oil were evaluated for the efficiency of encapsulation, morphology and size distribution of diameter, FTIR-ATR and X-ray diffraction, as well as for the release of carotenoids in gastrointestinal conditions in vitro. At the concentration of 30% zein, continuous ultrafine fibers were obtained, without bead formation and with mean diameter distribution ranging from 618 to 971 nm, whose encapsulation efficiency was higher than 77%. The FTIR-ATR analysis showed the encapsulation of the oil, and X-ray diffraction showed the amorphous structure of the fibers. It was verified that the composite fiber of 30% of zein and 30% of oil had a release profile close to the ideal of carotenoid release under simulated gastrointestinal conditions.