Abstract:
In the present study, the influence of buckwheat flour and carboxymethyl cellulose (CMC) on the production of sheetable gluten-free cookie dough of acceptable rheological properties and subsequently their effect on the quality of gluten-free cookies was studied. The buckwheat flour was used to replace 10, 20 and 30 % of rice flour in gluten-free formulations. Cookie doughs of 100 % rice flour and 100 % wheat flour served as control samples. The impact of CMC addition was examined on formulation containing 20 % of buckwheat flour. Oscillatory and creep measurements were applied to test the effect of buckwheat flour and CMC on the viscoelasticity of gluten-free cookie dough. Frequency sweep results showed that all samples had solid elastic-like characteristics. An increase in the buckwheat flour addition led to a decrease in storage modulus and zero shear viscosity and an increase in tan δ and maximum creep compliance, while the addition of CMC led to an increase in dough tenacity and resistance to deformation. Cookie dough containing 30 % of buckwheat flour expressed the highest viscous properties, as revealed by relative viscous compliance value. The gluten-free dough containing CMC and buckwheat flour between 20 and 30 % replacement level showed similar strength and extensibility as wheat cookie dough. The results of the physical and sensory evaluation of gluten-free cookies showed that buckwheat addition led to a decrease in cookie hardness and fracturability and an increase in eccentricity (deformation from regular shape) as well as the overall acceptability, as evaluated by untrained panellists.
