Fabrication of algal oil powder from pea protein-EGCG complex-stabilized emulsion template for structured antioxidant oil system

Abstract

In this work, we evaluated the potential of algal oil powders as structured antioxidant oils by stabilizing emulsion templates with pea protein (PP)- Epigallocatechin-3-gallate (EGCG) complexes. Turbidity, fluorescence, isothermal titration calorimetry (ITC) measurements indicated that the formation of PP-EGCG complexes and the interaction between PP and EGCG was caused by non-covalent binding. Furthermore, small-angle X-ray scattering (SAXS) measurement shown that the PP-EGCG complexes have smaller size and partial folding occurs internally. Compared with PP, PP-EGCG complexes have lower interfacial tension at the oil-water interface, an indication of better emulsification capacity. The physical storage stability of the emulsion was improved due to the smaller droplets of the emulsion stabilized by the PP-EGCG complexes. In addition, the agglomeration phenomenon of algal oil powder was weakened with increasing the mass ratio of EGCG/PP. The oxidation stability of the algae oil powder prepared from the PP-EGCG complex stabilized emulsion is improved, as evidenced by the decreased amount of the main oxidation product (hydrogen peroxide) and the by-product (hexanal). This study shown that PP-EGCG complexes can be used for construct stabilized emulsions templated oil powder for structured antioxidant oil system.