The influence of starch hydrolyzate on physicochemical properties of pastes and gels prepared from oat flour and starch

Abstract Materials used in this research were residual oat flour and starch isolated from it, and wheat flour and starch were used as reference. Pasting temperature of the starch present in flour or isolated starch increased with increasing syrup concentration, depending on material and syrup concentration. The maximum values of oat flour and starch paste viscosity were achieved at 30–40% syrup concentration, and at 50% for wheat pastes. Oat flour and starch pastes were pseudoplastic shear thinning fluids. In presence of syrup they revealed lesser deviation from Newtonian properties. Mechanical spectrum analysis of oat flour and starch pastes revealed stronger elastic than viscous properties. The hardness of flour gels prepared in syrup was higher than aqueous ones, and was increasing with increasing syrup concentration. It was stable during 7 days of storage. Adhesiveness of oat flour gels with syrup were lower than aqueous ones, reverse situation was observed for wheat flour gels. During storage, oat gels showed an increase of adhesiveness, in contrast to wheat gels, that were characterized by only initial increase of adhesiveness.