Sobowale SS, Bamgbose A and Adeboye AS
Matured green plantain (Musa paradisiaca) was processed into plantain flour and composted with wheat flour prior to extrusion. In this study, the effect of extrusion cooking variables [Barrel Temperature (BT, Feed Moisture Content (FMC) and Screw Speed (SS)] on the extrudate properties of whate-plantain noodles were investigated, while predictive models were also developed. Results obtained showed that changing the cooking variables significantly (p ≤ 0.05) affected all the extrudate properties studied. An increase in the screw speed (6.3-8.4 m/s) and feed moisture content (40-50%) resulted in a substantial increase in the expansion ratio (48%), residence time (62%) and specific mechanical energy (83.6%) Likewise, an increase in barrel temperature increased the mass flow rate (64.5%) of the extrudates significantly (p ≤ 0.05). Regression analysis also revealed that the screw speed and the feed moisture content were the major extrusion cooking variables, as they showed significant (p ≤ 0.05) linear quadratic and interaction effects on mass flow rate, residence time, specific mechanical energy and expansion ratio. The study showed that optimization of the combined effects of a 50% feed moisture content, 6.3 m/s screw speed of 6.3 m/s and a 100°C barrel temperature gave the optimum processing conditions for expanded wheat-plantain noodles. These variables are important considerations for commercial and mass production of wheat-plantain noodles.