Quality Evaluation of Doughnut from Wheat, Bambara Groundnut and High Quality Cassava Flour Blends

Abstract

This study was carried out to evaluate the quality characteristics of doughnuts produced from composite flours of wheat, bambara groundnut and high quality cassava flour (HQCF) blends. The functional properties of the flour; proximate, physical and sensory properties of the doughnut samples were determined. Five doughnut samples were prepared with sample A containing 100% wheat flour serving as the control. Sample B contained 85% wheat flour: 5% bambara groundnut flour: 10% high quality cassava flour; Sample C (80% wheat flour: 10% bambara groundnut flour: 10% HQCF); Sample D (75% wheat flour: 15% bambara groundnut flour: 10% HQCF) while Sample E contained 70% wheat flour: 20% bambara groundnut: 10% HQCF. Functional properties revealed that oil absorption capacity ranged from 0.91 to1.01%, water absorption capacity ranged from 0.81 to 1.01%, bulk density ranged from 0.67 to 0.73g/cm3 while swelling capacity ranged significantly (p<0.05) from 3.02 to 4.81%. The proximate composition showed a progressive increase in crude protein (10.83-14.11%), crude fat (11.01-27.37%), ash (0.33-1.53%), moisture content (19.88-32.75%) and crude fibre (3.83-4.26%) while carbohydrate content decreased significantly (p<0.05) from 54.12 to 22.05% with higher levels of bambara groundnut flour inclusion. Physical parameters revealed slight but significant variations with weight ranging from 101.3-105.0g, diameter 10.95-11.95cm, thickness 2.10-2.70cm and spread ratio 4.00-5.40. Sensory evaluation revealed high acceptability across all attributes with mean scores between 8.13 and 8.73. Sample C received the highest ratings for all the attributes. The study revealed that the inclusion of Bambara ground nut and HQCF in doughnut could promote food security by reducing the nation’s dependence on imported wheat flour. This study also concluded that substituting wheat flour with bambara groundnut flour and HQCF as locally sourced, healthier alternatives to wheat only products improved the functional, nutritional and sensory qualities of doughnuts without adversely affecting physical attributes.