Rheological properties of doughs obtain from quinoa/wheat flour mixtures within non-linear region

High-protein but gluten-free quinoa flour which mixed with wheat flour in different amounts can be used in baking products such as bread. However, gluten-free products do not have the same textural quality as wheat flour products. For this reason, in this study it was aimed to determine the non-linear rheological properties of wheat flour which is substituted up to 40% with the quinoa flour, instead of completely removing wheat flour and to determine the technological properties of the breads produced from these doughs. For this reason, Large Amplitude Oscillatory Shear test (LAOS) was applied; non-linear behaviors of wheat flour and 10%, 20%, 30% and 40% quinoa flour containing dough were investigated. A deformation (from %0,005 to %200) was applied to the dough samples at 10 rad/s frequency to obtain storage and loss modulus (Gʹ and Gʺ, respectively) values. Also, elastic (e3/e1), and viscous (v3/v1) Chebyshev coefficients were calculated using the Chebyshev polynomials and Fourier transformation (FT-rheology). Then doughs were baked and weight, volume, color, texture and sensory analysis of these breads were carried out. Farinograph analysis showed that water absorbtion capacity increased with the increase of quinoa flour. With rheological analysis carried by LAOS, it was observed that as the quinoa ratio increased, G'and G" values increase. These modules of all doughs began to fall, with increasing values of strain. Initially, the elastic modulus values were higher than the viscous modulus values but this situation was reversed after increasing a certain strain value. The FT rheology results of all samples showed non-linear zone and strain stiffening behavior with a strain of 0,05%. Also v3 values showed v3>0 (shear thickening) up to a point where strain was 1,26% and at higher values, it transformed to v3<0 (shear thinning), as could be observed by the use of LAOS module. The bread volumes showed a decrease with increasing quinoa content. Textural analysis showed that there was an obvious difference in the hardness of the breads, and the hardness increased in proportion to the increased ratio of quinoa. The color analysis demonstrated that the highest L* value (the lightest bread color) was in the wheat flour (control), and the lowest L* value (darkest color) was in the bread containing 40% quinoa flour. As a result of the sensory analysis, breads were found to be acceptable by taking an average score of 3,5 out of 5. In conclusion, in this study, the behavior of the dough with high deformation was evaluated in terms of contributing to baking technology. Wheat flour was substituted with quinoa flour up to %40, and it showed that its rheological and technological properties are acceptable in terms of producing the products with desired quality characteristics.