The Effect of Extrusion Variables on the Colour of Dakuwa Extrudates Produced from Blends of Sorghum (Sorghum bicolour L) Groundnut (Arachis hypogea L) and Tigernut (Cyperus esculentus L)
Mohammed Yusuf *
Department of Food Science and Technology, Modibbo Adama University of Technology Yola, PMB 2076 Yola, Nigeria
*Author to whom correspondence should be addressed.
Abstract
A three factor three level full factorial experimental design was used to determine the effect of extrusion variables on the colour of the extrudate with (90, 100 and 110°C) barrel temperature (50:20:30, 20:25:25 and 50:30:20) feed composition for ratios of sorghum groundnut and tiger nut respectively at 150rpm screw speed and 3 mm die diameter using a twin screw food extrusion coocker (SLG-65-III Model China). Version 16 of Genstat was used in analysing the result. The result reveal that extrusion significantly (p<0.05) affect the colour of the extrudate. The total colour differences between the extruded samples (ΔE) were determined. The average ΔE values ranged from 7.13 to 38.82. Statistical analysis showed that the barrel temperature feed composition and feed moisture content had an effect on the total colour differences (P<0.05) of Dakuwa extrudates. The highest ΔE was found at 90 oC barrel temperature, 50:25:25 feed composition and 22% feed moisture content.
Keywords: Colour, extrusion, dakuwa extrudates