Effect of Extrusion Conditions on Nutrient Status of Ready-to-Eat Breakfast Cereals from Sorghum-Cowpea Extrudates

Sorghum and cowpea flour mixes (90:10, 80:20 and 70:30 ratios respectively) were extruded at 20%, 22.5% and 25% moisture levels and 120 °C, 140 °C and 160 °C barrel temperatures using a singlescrew extruder. A central composite face-centered design was used to study the effects of feed composition, feed moisture and extrusion temperature on the proximate composition and essential aminoacids of the extrudates. Results obtained showed that the energy, carbohydrate, protein, moisture, fat, ash and crude fibre content of the extrudates increased from 363.63 to 379.15 kcal, 70.19 to 77.55%, 13.20% to 17.80, 5.50 to 7.90%, 1.55 to 1.75% and 1.60 to 2.80% and 2.10 to 2.72% respectively. Lysine content of the extrudates increased from 5.46 to 7.27 g/100 g, while methionine ranged from 1.05 to 1.85 g/100 g. There was significant (p?0.01) increase in the protein and amino acid contents of the extrudates due to supplementation with cowpea flour.