Prior roasting of wheat impacts on the functionality of flour prepared from it: Part 2. Wheat protein functionality

Abstract

Background and Objectives:In the accompanying paper (van Rooyen et al., submitted), it was reported that forced convection roasting of wheat prior to milling can be directed to tailor the viscosifying properties of flour. The objective of the present work was to examine the effect of prior wheat roasting on flour proteins.Findings:Effective control of wheat roasting conditions proved to be essential to avoid the irreversible loss of flour functionality as deduced from the flour ethanol and lactic acid solvent retention capacity and mixography data. Response surface models predicted roasting at 108°C and 80 Hz (135 s) to maintain protein integrity. The microstructure of flour and isolated starch as well as X‐ray diffraction pattern revealed starch to be relatively unaffected by heat treatment.Conclusions:Flour produced from roasted wheat can still be used for products that require the formation of a gluten network.Significance and Novelty:Protein is more sensitive to roasting conditions than starch.This article is protected by copyright. All rights reserved.