DEVELOPMENT OF A DOUBLE ACTING CASSAVA GRATING MACHINE

ABSTRACT

Cassava is a major source of carbohydrate for human food and Nigeria is a major producer of this product, it is almost eaten daily by most families in the country. In recent times, cassava is cultivated as food crop and is one of the major foreign currency earner. Cassava processing involves peeling, grating, de-watering, fermenting, sieving, frying, and drying. Grating cassava tubers into pulp form is also a major means of processing this product into finished food sources. However, the use of a single grating machine still requires a re-introduction of semi-grated pulp in the machine. Hence the need for a double acting cassava grater; which can reduce the extent of corrosion using stainless steel, and a model design where one module feeds the other to produce proper grinding of cassava pulp. The double acting cassava grating machine was made using locally sourced materials such as stainless steel, mild steel, pulley, belts, bearings and driven by a 1 kilowatts electric motor. Already peeled cassava is introduced into the first hopper; compressed by a spring enhanced cover, grinding takes place in the first hopper and the cassava pulp is re-introduced into the second hopper for second stage grinding. The machine was tested, and results obtained showed that it grated 17.78, 17.98 and 18.20 kilograms of cassava tubers in given times of 152, 160 and 185 seconds with the output paste uniquely smooth in all batch grating. The machine efficiency was calculated based on its mechanical advantage and velocity ratio as well as its output/input load ration and was found to be 91 percent efficient which makes it very suitable for the grating of cassava tubers and can be used anywhere in Nigeria