Effect of a pH shift treatment on the functional properties of individual and blended commercial plant protein ingredients

The overall goal of this study was to investigate the effect of pH shifting on the functionality of pea, rice, oat, and hemp proteins and their blends (pea:rice, 60:40; pea:oat/hemp, 50:50). Proteins were processed at pH 2 or 10, with and without heat (80 degrees C), followed by neutralization at pH 7 and then spray dried. Depending on the protein source and pH treatment changes in the functional properties were observed. Solubility of all untreated samples was improved by at least one of the pH shift treatments whereas foaming stability was not. pH 10-heat-treated oat protein had the highest water-holding capacity at 5.71 g/g compared to 0.77-4.16 g/g for the other proteins. Only oat and hemp showed improved OHC after acidic or alkaline treatment. Emulsion stability was maximized in the pea-rice/oat blends after alkaline treatment, with or without heat. Blending proteins and subjecting them to pH shift treatment can result in unique functionalities that could be tailored to specific food applications.