Design, Fabrication and Testing of a Manual Juice Extractor for Small Scale Applications

Abstract

Transformation of locally produced fruits into juice helps to enhance profitability in orchard farming. Several fruit juice extractors exist but there is need to make available juice extractor that has low production cost. This is to ensure that they are readily available and affordable for local fruit processors. A manually operated juice extractor was designed and fabricated using locally sourced materials. The extractor consists of a feeding unit, extraction unit, juice collector, waste outlet, frame and bearings. Polytetrafluoroethylene (PTFE) a synthetic fluoropolymer was used in the construction of the screw shaft and stainless steel for the extraction chamber. Rotational motion needed by the screw shaft to compress and transport the fruits was supplied manually to the machine through a handle. The screw shaft crushes, squeeze and facilitate the movement of residues to the waste outlet while the juice passes through the screen to the juice collector. Tests were carried out to investigate the performance of the machine on the basis of juice yield, extraction efficiency and extraction loss. The efficiencies obtained were 57%, 53.6% and 52.9% for water melon, tangerine and pineapple respectively. The extraction efficiencies for water melon, orange and pineapple were 71.3%, 65.8% and 63.8% respectively. The extraction losses for water melon, orange and pineapple were 2.5%, 4.3% and 3.5% respectively. The capacities of the machine for watermelon, orange and pineapple were 19.51 kg/hr., 15.97 kg/hr. and 18.10 kg/hr. respectively. The juices produced from the extractor are of good quality which further proves the effectiveness of the extractor. The manual fruit juice extractor is cheap, durable and cost of operation is low and could be used by an average Nigerian household and small scale farmers.