Fabrication and characterization of soybean oil bodies encapsulated in maltodextrin and chitosan-EGCG conjugates: An in vitro digestibility study

Plant lipids are mostly stored in subcellular organelles known as oil bodies (OBs). The aim of this study was to encapsulate soybean OBs by spray-drying, in order to offer a prospective approach to stabilizing OBs, and to provide a novel spray-dried OB product for potential industrial uses. OB emulsions were prepared with different coatings, namely maltodextrin (MD), chitosan (CS), and CS-EGCG covalent conjugates (CSEG), prior to spray-drying. The highest encapsulation efficiency of 96.68% was achieved for MD-CSEG encapsulated OB microparticles. Morphological analysis of spray-dried samples revealed that encapsulating OBs resulted in remarkably reduced microparticle sizes, even after reconstitution. Furthermore, the CSEG provided an even more effective interfacial barrier that protected OB microparticles. In vitro gastrointestinal digestion results revealed that coating OB with MD and CSEG greatly retarded the oil release from 85.2% to 45.3%. This study demonstrated that this novel encapsulation formulation of OBs has the potential to overcome stability drawbacks and minimize the degree of oil release throughout digestion.