Wheat flour starch granule-size distribution and rheological properties of dough. Part 4. Farinographic measurements

To examine how granulometric composition of wheat flour starch affects the rheological properties of dough in conditions of farinographic measurement, the content of starch fractions, i.e. the granulometrical and statistical parameters of granule-size distribution determined previously (Nahrung 39 (1995) 106), were correlated with farinograms evaluated after AACC and ICC criteria as well as after criteria proposed by PR ITER et al. (Bull. Sci. Sect. A Yougosl. 21 (1976) 217)and suggested as the most exact ones. Data show that fraction of very small granules causes weakening of dough while the most represented granules sized 5-16 mu m in diameter (mean content 47.3%) influence the shape of the first part of farinographic curve causing dough development time, stability, time to breakdown and quality number to be higher. The higher the content of larger granules (16 mu m) the lower the softening of dough and farinographic area. The higher the mean value of granules' size the higher the time to breakdown and the lower dough weakening; the higher the most frequently occurring granule size the smaller the degree of weakening of dough and farinographic area. Significant correlation between parameters of farinogram and different statistical, i.e, granulometrical parameters of granule-size distribution (0.05 P 0.005) confirm that granule-size distribution can affect behavior of dough during mixing in the farinograph.