ABSTRACT
This study investigated the effect of extrusion process on engineering properties of noodles analogue from water yam, yellow maize, and African yam bean. Flour blend from water yam, yellow maize, and African yam bean were produced using the standard method of dry milling and was used to extrude noodles analogue using a brabender single screw laboratory extruder (Duisburg DCE 330 model) fitted with 3.0mmdie nozzle diameter. A central composite rotatable design (CCRD) with three variables, namely barrel temperature, feed moisture content and screw speed and five level coded – a, -1, 0, +1,, +a, was used for the study and data was generated at (p<0.05). Results of result of the engineering properties of noodles analogue showed that toque ranged from 22.4 to 60.50Nm/s, mass flow rate ranged from 33.90 to 109g/min-1, specific mechanical energy ranged from 100.19 to 385.97kj/kg, and the residence time ranged from 22 to 55s in this study. The CCRD was effective in explaining the effect of the process conditions on noodles analogue as influenced by barrel temperature, feed moisture content, and screw speed of the extruder. The data obtained from the study could be used for control of product characteristics.It was generally observed that the changing of feed moisture content, barrel temperature, and screw speed influenced an acceptable torque, mass flow rate, and residence time during the extruder operation. The noodles analogue produced at this cheap machine operating conditions could be projected for commercial production.