Evaluation and storage studies of sausage roll produced from wheat-tigernut flour blends

This study was carried out to investigate the effects of wheat flour substitution with tigernut flour. Brown variety of tigernut was sorted and dried in a cabinet dryer at 60°C for 72hrs and was processed into flour and blended with wheat flour at different ratios of 100:0; 90:10; 80:20; 70:30; 60:40; 50:50, 40:60, 30:70, 20:80, 10:90 respectively. The flour blends were analyzed for proximate composition, functional properties, pasting properties and rheological properties (viscosity). Data obtained were subjected to analysis of variance and significant means were separated using Duncan multiple range test. Moisture, crude protein, crude fibre, total ash, crude fat and carbohydrate ranged from 4.11 to 10.35%, 4.72 to 12.28%, 2.82 to 9.81%, 0,51 to 0.78%, 0.84 to 15.61% and 50.26 to 73.25% respectively. Significant differences exist in the functional, pasting properties and viscosity of wheat and tigernut flour blends. As the substitution of tigernut flour increases, the hardness, crust and crumb moisture of the sausage increases during storage. The result of this study shows that tigernut has the advantage of improving the crude fat, total ash and crude fibre of the blends. Substitution of tigernut flour to wheat flour had a significant effect on all the functional properties of the flour blends. The pasting properties of wheat and tigernut flour blends were affected thereby leading to decreases in the peak, trough, breakdown, final viscosity, setback and peak time. The viscosity of wheat and tigernut flour blends is relatively too high and this suggests that the flour blends will be useful in production of baked products.