Cowpea-wheat Value Added Products Development and Quality Evaluation
No Thumbnail Available
Date
2017-10
Authors
Journal Title
Journal ISSN
Volume Title
Publisher
Addis Ababa University
Abstract
The study was conducted in order to develop products with bole type-cowpea flour incorporation in to wheat flour (Mangudo) to achieve nutritional quality product and to reduce celiac problem which is arise from gluten content of wheat flour. The blended flour of wheat (mangudo variety ) and bole type cowpea flour were prepared in ratio of B1(90,10), B2 (40,60), B3 (65,35), B4 (78,22), B5(53,47),B6(100,0)(control), respectively with D-optimal design software. In this study; grain quality analysis, blended flour (physical, functional and proximate composition) analysis, physical and functional properties, proximate composition, mineral analysis, microbial load determination, bioactive component and sensory evaluation of biscuit and flake extrudet products were investigated. The biscuit samples were prepared with each blended flours dough at 205 0C oven temperature for 10 minutes. The bulk density, water absorption and water solubility index, fracture strength, proximate and microbial load were determined. Bulk density ( 0.701g/cm3),water absorption and water solubility index(203.26 &23.383%), fracture strength (10.58N), proximate composition( moisture:5.392%, wb, crude fiber:2.2%, Fat:11.632%, crude protein:15.972%, ash:1.93%, carbohydrate:62.872%),microbial load (aerobic bacteria:44* 10-5 cfu, yeast and mold: un-detected) of biscuit sample B3 (65% wheat and 35% cowpea flour). The highest overall sensory evaluation score of biscuit sample was 7.6 comparable with like very much (B3) next to the control sample B6. The extrudet also prepared with twins screw extruder parameter on barrel temperature (100, 110 and 120°c), feed moisture (18 and 21%) and screw speed (175 and 220 rpm) after determined the flour flow screw speed rpm and water pump stoke level. Proximate composition and microbial load of flake extrudet sample (Ex-3) were determined. Proximate composition (moisture: 6.35%, wb, crude fiber: 2.22%, fat: 0.67%, crude protein: 15.915%, and carbohydrate: 72.34%) and microbial load (aerobic bacteria: 42*10-5, yeast and mold: un-detected). The highest overall sensory evaluation of extrudet score was 7.14 (Ex-3) which was above like moderately next to the control Ex-6. Based on the sensory result and further analysis, cowpea flour could substitute 35% of wheat flour in biscuit and flake extrudet product development with better nutritional quality.
Description
Keywords
cowpea, wheat, extrusion, biscuit, D-opti