ABSTRACT

An automated gartification machine comprising a feed hopper, cassava mash metering mechanism, toasting trough, paddle screw conveyor, heating chamber, charcoal stove, air blower and discharge chute was designed, fabricated and evaluated. The machine is powered by 1Hp single phase electric motor fitted with a variable speed reducer and automatically controlled by two limit switches connected to forward and backward contactors which actuate the forward, stop and reverse movement of the paddle screw conveyor, enabling to and fro movement of the cassava mash along the toasting trough during garjflcation process. The results of its performance test indicated 21.30kg/h, 92%, 386.77kJ/kg and 60.08% as the throughput, throughput efficiency, specific energy consumption and energy utilization efficiency of the machine respectively. Also, the operational speed of the paddle screw conveyor at these performance indicators is 20rpm. The gari produced from this machine has a moisture content, acidity level, grain size and swelling index of 11.96%, 0.63%, 2.0mm and 3.71 respectively, which are in line with the standard values of 12% (max), 0.6%-1.0%, 2mm and 3-5 for moisture content, acidity level, grain size and swelling index respectively as recommended by Codex Standard 151-1989. The garflcation machine fabricated with standard and locally sourced materials eliminated the problems encountered in the manual operation and the existing machines, produced gari of the desired and acceptable quality and in commercial quantity at a fast rate. The machine is energy saving and affordable due to its low cost of One Hundred and Eleven Thousand, Six Hundred and Fifty Naira (N 111,650:00).