Factors affecting rheological properties of barley flour-derived batter and dough examined from particle properties

Barley use as flour is attracting interest. However, the factors affecting barley batter and dough rheological properties related to the water adding ratio adjustment are unclear. To promote the development of barley flour products, we aimed to clarify the factors that influence the rheological properties. This study focused on particle properties, including not only particle size and its distribution, but also damaged starch and void fraction. Three barley flour samples of different particle properties were ground by a hammer mill using different nominal screen opening sizes mounted on the mill. The effect of the particle properties differed by water addition ratios, occurring on the batter (water addition of 200%–300%), but not the dough (water addition of 100%–150%). The particle size is suspected to affect batter rheological properties by regression analysis. Accordingly, β-glucan was eluted in the barley batter dispersion medium: its elution amount and the dispersion medium viscosity were different depending on the particle size, that is, the specific surface area by comparing the dispersion medium and the fluorescence observation of β-glucan in the barley batter. Based on the abovementioned observations, particle size and associated β-glucan elution difference was the factor suggested to affect barley batter rheological properties: smaller particle sizes increased the eluted β-glucan concentration and the yield stress and dynamic viscoelasticity were increased. A dispersed particle state model was created using the results.