Influence of water and barley p-glucan addition on wheat dough viscoelasticity

摘要

The effects of the addition of two barley β-glucan isolates (0.2-1.0% of wheat flour), differing in molecular weight, and water (53-63% in a poor breadmaking wheat flour, cv. Dion, and 58-68% in a good bread-making wheat flour, cv. Yekora) on the viscoelastic properties of wheat flour doughs were investigated. A response surface model (CCF) was used to evaluate the effects observed on the dynamic and creep-recovery parameters of the dough. The evaluation was done separately for each combination of β-glucan isolate (BC1 of ～10~5 Da and BG2 of ～2 × 10~5 Da) and flour type. Besides the contents of β-glucan and water, the molecular size of the polysaccharide and the flour quality were important determinants of the dough's viscoelastic behavior. Compared to BG1, the higher molecular weight β-glucan (BG2) brought about major changes on all the rheological responses of the fortified doughs. The addition of appropriate levels of β-glucans and water in the poor breadmaking cultivar (Dion) doughs could yield similar viscoelastic responses to those observed by a non-fortified good breadmaking quality flour dough (Yekora).