Fabrication of Resveratrol-Loaded Whey Protein-Dextran Colloidal Complex for the Stabilization and Delivery of β-Carotene Emulsions.

The effects of resveratrol (RES)-loaded whey protein isolate (WPI)-dextran nanocomplex on the physicochemical stability of β-carotene (BC) emulsions were evaluated. WPI-dextran was prepared by Maillard-based glycation and confirmed with gel electrophoresis and OPA assay. WPI-RES and WPI-dextran-RES nanoparticles were prepared with a simple nanocomplexation protocol. Fluorescence spectra indicated that hydrophobic interaction was the main driving force for the WPI-dextran-RES nanocomplex. Spherical and uniformly dispersed structures as well as nanoscale Z-average size (<100 nm) were confirmed for WPI-RES and WPI-dextran-RES nanocomplex with DLS and TEM. The Z-average diameter of emulsions with WPI-dextran conjugate was remarkably lower than that with WPI. Environmental stress (ionic strength, heat, and pH) and storage stability were pronouncedly improved. The chemical stability of BC with WPI-dextran-RES and WPI-RES was also remarkably enhanced when exposed to UV light and thermal treatment. The advantages of the WPI-dextran-RES colloidal complex may provide a better alternative to effectively protect and deliver hydrophobic nutraceuticals.