Rheological, baking and sensory characteristics of fermented cassava starch-wheat-cowpea blends

Abstract

The rheological, bread making and sensory attributes of varying replacement levels (0-30%) of wheat flour (WF) by fermented cassava starch (FCS) and WF-FCS blends fortified with cowpea flour (CPF) were evaluated. Dough stretchability remained unchanged up to 10% replacement level of WF by FCS. The energy for dough deformation (W),decreased from 316.1x10-4 Joules/g in 100% WF to 275.8x10-4 Joules/g at 20% WF replacement level. Fortification of WF-FCS blends at higher dilutions (30% replacement level) with cowpea flour gave alveograph values that were comparable with the 70:30 (w/w)% WFFCSmixture but with improved R/L ratio. WF-FCS and WF-FCS fortified with CPF had high gelatinization temperatures (61.4-79.10C) and 71.4-82.10C respectively. Peak and cooked paste viscosities increased with increasing contents of FCS. Protein contents of composite breads ranged from 6.3-9.3%. No significant difference (P>0.05) was observed in the bread characteristics of loaves preparedwith 70:30 (w/w)% WF-FCS and samples fortified with 5 and 9% CPF. Breads made from 5-10% FCS supplemented WF showed no significant difference (P>0.05) from control (100% wheat bread) in sensory panel ratings for crust colour, crumb colour, crust texture, flavour/aroma and overall acceptability characteristics. Up to 20% substitution withFCS (80:20 (w/w)% WF/FCS) and 5% fortification with CPF (70:25:5) produced breads with acceptable loaf volume, specific volume and organoleptic characteristics.