Study of chia oil microencapsulation in soy protein microparticles using supercritical CO2-assisted impregnation

Abstract

Microencapsulation of chia oil in soy protein microparticles was achieved using supercritical CO2-assisted impregnation, an alternative green technology. The effect of the process variables on retention and encapsulation efficiencies was studied. The characterization of the chia oil-loaded microparticles showed excellent encapsulation efficiency, a spherical shape with some depressions but without pores or fissures, sizes between 1 and 10μm and homogeneous oil distribution. The hydroperoxide values and fatty acid profile indicated that the microencapsulation process did not affect the chemical quality of the oil. In addition, a study of the influence of storage time showed excellent oxidative stability for microencapsulated samples compared to free oils, with the microparticles providing a remarkable protective effect that enhances the useful life of the product. It was determined that 95.69±4.28 % of the oil was released under gastro-intestinal conditions, mainly in the intestinal step, remaining available for absorption.