Quinoa Proteins Isolate, a Candidate for Functional Ingredients Design.

The objective of the present contribution was to design and characterize resveratrol (RSV) and tocopherol (TOC) loaded quinoa protein (QP) nanocomplexes, their antioxidant and antiradical functionality were also evaluated. QP intrinsic fluorescence spectra showed a quenching effect exerted by RSV and TOC, demonstrating protein-bioactive compounds interactions. Stern-Volmer and Scatchard models application confirmed the static quenching effect and allowed to obtain parameters that described the QP-RSV or QP-TOC complexation process. Isothermal titration calorimetry allowed obtaining thermodynamic parameters to describe the interaction between RSV or TOC with QP. Protein aggregates up to 40 nm in diameter were induced by bioactive compounds as detected by atomic force microscopy. QP-RSV and QP-TOC nanocomplexes showed additive effect in their antioxidant capacity. These nanocomplexes could constitute a real platform for the design of functional ingredients.