Genetic variation in wheat grain quality is associated with differences in the galactolipid content of flour and the gas bubble properties of dough liquor

Byoung Min,Louise Salt,Peter Wilde,Ondrej Kosik,Kirsty Hassall,Alexandra Przewieslik-Allen,Amanda J Burridge,Mervin Poole,John Snape,Luzie Wingen,Richard Haslam,Simon Griffiths,Peter R Shewry

doi:10.1016/j.fochx.2020.100093

Abstract

Lipids affect the quality of wheat flour for breadmaking. One possible mechanism is stabilization of the gas cells which are formed during dough mixing and expanded during fermentation, leading to a greater loaf volume and evenness of texture. We therefore compared the lipidomic profiles of flour and dough liquor fractions (which contain surface-active components present at the gas bubble interface) from two sets of wheat lines differing in allelic variation at a QTL for loaf volume. Analyses of fractions from three field trials showed consistent increases in the contents of galactolipids (monogalactosyl diglyceride and digalactosyl diglyceride) in flour and dough liquor of the lines with the increasing (good quality) allele. Biophysical analysis showed that this was associated with greater elasticity of the dough liquor fraction. This is consistent with published studies reporting a relationship between galactolipids and breadmaking quality and suggests a mechanism of action for the QTL.

Highlights

Wheat is the third most important cereal crop in terms of global production and the dominant crop and major staple food in temperate countries, where it contributes between 20% and 50% of the total calories in the human diet
We compared the lipidomic profiles of flour and dough liquor fractions from two sets of wheat lines differing in allelic variation at a QTL for loaf volume
It is due to the grain processing properties, and in particular the ability of wheat flour to be processed into bread, other baked products, pasta and noodles

Summary

Introduction

Wheat is the third most important cereal crop in terms of global production and the dominant crop and major staple food in temperate countries, where it contributes between 20% and 50% of the total calories in the human diet. When flour (milled grain) is mixed with water these proteins interact to form a continuous viscoelastic network which provides the cohesion required for making pasta and noodles and enables the entrapment of carbon dioxide released by bakers’ yeast during proofing to give the light porous crumb structure of leavened bread Because of their functional importance wheat gluten proteins have been the subject of an immense volume of research dating back to the mid-18th century (Shewry et al, 2009; Hamer, MacRitchie, & Weegels, 2009) gluten proteins are not the sole determinant of processing quality and other grain components have impacts, including starch and cell wall polysaccharides. The increasing fluctuation in growing conditions associated with climate change has emphasised the importance of improving the stability of processing quality which is likely to be affected, either positively or negatively, by minor grain components as well as gluten proteins

Methods

Results

Conclusion