Design and Performance Evaluation of Cassava Fibre Removal Machine for Fufu Production

Abstract

This research work was carried out to design and evaluate the performance of a cassava fibre removal machine capable of efficiently removing insoluble fibres from fermented cassava and retaining the starch slurry used for the production of a fufu or akpu (cassava dough) a common staple food in West and Central Africa. Traditional cassava processing methods is labour-intensive, time-consuming, inefficient and often leave residual fibers in the cassava slurry, reducing product quality and increasing processing time. Processing of cassava is necessary for several reasons: it reduces or removes the potentially dangerous cyanogenic glucosides found in raw cassava and provide more options for consumer’s diets. Materials of right strength and sizes for the machine parts were determined and selected based on the design analysis and calculations carried out. Drum, conical water chamber, frustum screen, gear box, stirrer shaft, frame and discharge chute are the main components of the machine. Several cassava processing machines and method of removing insoluble fibre from cassava have been developed globally; however, some are not cost-effective for use in small-scale operations but rather for large industrial scale; others have negligible efficiency, low throughput capacity, high percentage of loss, and contamination of the food due to mild steel’s propensity to rust over time and subsequently degrade processed product quality. In this research, the developed machine performance evaluation was based on the effect of the insoluble cassava fiber removal in the drum, and retention of the cassava slurry in the conical chamber, encompassing different fermented cassava mash variation (5, 10, 21, 30 and 35kg) and residence time on key performance indicators (proportioned by weight of fermented mash, separation efficiency and throughput capacity). The machine operated at a reduced speed achieved by a 2.6Hp prime mover through a reduction gear mechanism, exhibited commendable performance, resulting in an average fiber separation efficiency of 89.4% and average throughput capacity of 191.4kg/h under the tested operating conditions (5 – 35kg feed loads). The inclusion of a conical water chamber into the design facilitated efficient fractionation and creating of slurry that washes the fine starch granules down through the sieve mesh, ensuring a smooth, lump-free texture for fufu/akpu production, leaving the insoluble fiber, bran and chaff out. The results also unveiled that the developed machine is efficient, economical, user friendly, reduce drudgery and fatigue than the traditional methods commonly used by Nigerian fufu/akpu processors in the removal of insoluble fiber from fermented cassava.