Fractionation of plant proteins using deep eutectic solvents and high-pressure processing

Abstract

Increasing demand for desirable plant protein ingredients necessitates efficient fractionation methods to process plant materials into functional fractions optimized for specific food applications. Deep eutectic solvents (DES) can interact with proteins and alter their physical characteristics for sub-fraction separation. Pea protein concentrate (PPC) was extracted using DES-water mixture (ChCl/glycerol, molar ratio of 1:2, 60 % hydration) with heat (100 °C, 15 min) or high-pressure processing (HPP) (600 MPa, 5 °C, 5 min). Proteins were precipitated using isoelectric or anti-solvent methods. The proteins extracted were characterized by their extraction efficiencies, structural and functional properties. DES caused pea proteins to separate into two fractions with distinct denaturation peaks. While protein content of most sub-fractions (58.27-97.60 %) were comparable or higher than that of conventional extraction methods, extraction yields were significantly lower. Anti-solvent precipitation yielded legumin-rich sub-fractions which could enhance specific food applications, such as meat and dairy alternatives.

Keywords: Deep eutectic solvent; High-pressure processing; Plant protein; Sub-fractionation.