Effect of extraction rate on rheological properties of wheat flour

The effect of different extraction rates (64%, 82% and 90%) of wheat flour on the rheological properties of the wheat flour dough was investigated. A complete study of the rheological behavior of the wheat flour dough was performed by using three different instruments namely alveograph, extensograph, and farinograph. The correlation coefficient among the various parameters of applied methods was also determined and the most suitable method in assessment of flour attributes recognized. The lower bran concentration (extraction rate 64%) in flours showed the better pronounced effect on dough properties yielding strengthened dough. Several expected associations were found among applied methods, in spite of the fact that no significant correlation among all parameters of the methods was observed, some parameters of the measuring methods had very strong correlation (p<0.01) that included farinograph water absorption, tenacity (P), extensibility (L), P/L, swelling index (G) of alveograph, energy and the resistance to constant deformation after 50 mm stretching (R50) of extensograph. Among the applied methods, most of the alveograph parameters had significant correlation (p<0.01) together and it might be used as the recommended method to assess dough rheology.