Effect of flour production methods on the yield, physicochemical properties of maize flour and rheological characteristics of a maize-based non-fermented food dumpling.

Abstract

The study was aimed at investigating the influence of flour production methods (Grit Soaking Method [GSM], Grit Non-soaking Method [GNM] and Pestle and Mortar Dehulling Method [PMDM]) on the yield, physicochemical properties of maize flour and rheological characteristics of a maize-based non-fermented food dumpling. The flour yield from the production methods ranged between 56.6 and 62.3% with GSM and GNM giving the lowest and highest values respectively. There were variations in the mean particle size (203.3-220.5 µm) and damaged starch content (12.2-14.5%) of flours obtained from the three production methods. The flours from the production methods also exhibited variations in the pasting temperature (73.2-74.6oC), peak viscosity (84.2-110.6 RVU) and final viscosity (111.4-147.4 RVU). The lightness indices (L*-values) of the flours (88.8-90.0) and maize ‘tuwo’ (66.9-67.7) were affected by the flour production methods while the chroma (C-values) of the flours (14.6-14.9) and maize ‘tuwo’ (8.9-9.1) were also affected though not significantly different (p<0.05). The cohesiveness index (15.1-15.9%) and softness index (17.2-17.8 mm) of maize ‘tuwo’ prepared from the flours also exhibited variations.   Key words: Dumpling, flour, maize, 'tuwo', rheological characteristics.