Nanostructured soy proteins: Fabrication and applications as delivery systems for bioactives (a review)

Abstract Soy proteins as an important food ingredient have been widely applied in food formulations, due to their good nutritional value, high functionalities, and health-benefiting effects. Evidences have been fast accumulating to indicate that soy proteins are a kind of excellent building materials to be fabricated into a variety of nanostructured delivery systems for food bioactive ingredients. This review mainly presents the state-of-the-art knowledge about the fabrication of different kinds of nanostructures of soy proteins, as well as their applications to perform as nanocarriers for bioactives, achieved during the past decade. The composition, structure and physicochemical properties of soy proteins (including glycinin, β-conglycinin, and soy protein isolate) are first summarized. Then, the main strategies and techniques to fabricate a variety of nanostructured soy proteins are reviewed, including heat-induced aggregation, complexation with polysaccharides, emulsification-evaporatioin, desolvation/solvent displacement, crosslinking, self-assembly, electrospraying, nanoemulsions and interfacially nanostructured emulsions. Lastly, the feasibility of these nanostructured soy proteins (especially nanoparticles) to peroform as effective nanocarriers or delivery systems for bioactives are discussed. Due to the fast increasing interest of the food industry and consumer health awareness for the incorporation of soy proteins in functional food formulations, this review is of importance for guiding the development of novel ‘dual-function’ nanostructured soy protein-bioactive formulations.