Proximate Composition, Functionality and Pasting Properties of Orange Flesh Sweet Potato and Red Bambara Groundnut Flour Blends for Snacks Formulation

Abstract

Successful use of non-wheat flours for snacks production depends on their functional and pasting properties. The use of orange fleshed sweet potato and red Bambara groundnut flour blends for snack production have not been explored. The objective of this work was to formulate flour blends using orange fleshed sweet potato and red Bambara groundnut and to evaluate their proximate compositions and processing properties for possible application in the production of high protein and pro-vitamin A enriched snacks for consumers especially children in developing countries. Flour blends were formulated in ratio 60:40, 50:50, 40:60, 30:70 (orange fleshed sweet potato to red bambara groundnut). The protein and fat increased from 12.95±0.05% (60:40) to 16.87±0.02% (30:70) and 2.17±0.03% (60:40) to 3.05±0.04% (30:70) respectively. Ash and carbohydrate decreased from 2.52±0.04% (60:40) to 2.27±0.05% (30:70) and 60.38±0.44% (30:70) to 69.09±0.30% (60:40). The water absorption capacities for the flour blends ranged between 28.03±0.17% and 50.40±0.40%. Oil absorption capacity was between 16.70±0.12% and 31.40±0.13%. Swelling capacities was highest in 30:70 (2.48±0.06%) and lowest in 60:40 (2.13±0.07%). Solubility was between 9.27±0.59% and 11.67±0.70%. Bulk density ranged between 0.77±0.01 g/ml and 0.87±0.02 g/ ml. Peak, breakdown, setback and final viscosities increased from 92.88±3.47 to109.34±0.23; 20.33±3.66 to 21.75±1.17; 32.16±0.84 to 44.59±0.25 and 102.71±1.00 to 132.00±1.06 RVU respectively. This study indicate that the 50% sweet potato and 50% red bambara groundnut flour blend will make a better product judging from its functional and pasting properties compared to other blends but will require a little more energy to cook comparing their pasting temperature and time.