Genetical, Biochemical and Technological Parameters Associated with Biscuit Quality. I. Prediction Using Grain Hardness and Water Extractable Arabinoxylans

Abstract

The aim of this work was to identify the main biochemical and technological parameters that could be efficient in wheat breeding programs for biscuit-making quality. A semi-sweet biscuit was chosen as the standard biscuit for this study. Evaluation of biscuit-making quality was carried out with a set of 39 French cultivars. Thirty-six biochemical and technological characteristics were determined on this plant material. Variables obtained from the biscuit test were closely associated with grain hardness (GHa) and (to a lesser extent) with the viscosity (Visc) of water extractable arabinoxylans in flour. High molecular weight glutenin subunits (HMW-GS) and total proteins were also found to be linked to biscuit quality but had less effect than grain hardness and viscosity. Multiple regression analyses revealed that starch damage was highly correlated with grain hardness and explained 60·1% of variations in consistence, 70·5% in thickness, 76·6% in density and 51·9% of the rupture force of the biscuits. The heritability of ten biscuit-test parameters and ten flour characteristics was evaluated using a set of 19 cultivars grown in three different locations. All the parameters analysed (except surface appearance) were significantly influenced by the genotype, whereas location did not significantly affect machinability, thickness or surface appearance. Starch damage, laser granulometry, grain hardness, density and thickness of the biscuit displayed the highest heritability coefficients, 0·95, 0·94, 0·92, 0·92 and 0·90, respectively. Our results provide reliable information for designing wheat breeding programs to improve biscuit quality. Results also indicate that the creation of wheat cultivars to improve the quality of semi-sweet biscuits can be achieved through breeding programmes.