Journal of Agriculture and Food Research (Dec 2020)
Design, fabrication and performance evaluation of moringa (oleifera) dried leaves pulverizer
Abstract
Moringa oliefera (Moringapterygosperma Gaertner) leaves popularly known as ‘ewe igiiyanu’ in Nigeria. The current study is to develop a moringa oleifera leaves pulverizer from locally sourced materials. The proposed machine works with the shearing mechanism. The main features of the machine are coverer, auger, shaft, hopper, sprout, frame, belt, pulley, bearings and electric motor. The machine was designed, fabricated and tested fulfilling the all scientific standards During study, a solar dryer was used for drying moringa oleifera leaves at average temperature of 40–50 °C for 3 days, the solar dryer had five sets of trays arranged above each other in layers. After 3 days, the moisture contents for tray 1, tray 2, tray 3, tray 4, and tray 5 were estimated as 7.2%, 24.9%, 39.4%, 39.3%, and 45.9%. Two speeds 1000 rpm, 467 rpm of the motor was used for the evaluation of the performance of the machine, and the efficiency of the machine at these speeds was 91% and 96% respectively. Sieve analysis was used to get the fineness modulus and uniformity index of the pulverized leaves using the high and low moisture content of 45.96% and 7.17%. For 12.6 g (1000 rpm) of moisture content of 7.17% [FM:UI 3:: 6:2:2] and for 10.2 g (1000 rpm) of moisture content of 45.96% [FM::UI 4.9:: 6:4:0] for 9.6 g (467 rpm) of moisture content of 7.17% [FM::UI 3.8:: 5:4:1] for 10.9 g (467 rpm) of moisture content of 45.96% [FM::UI 3.13:: 4:4:2]. These results showed that 467 rpm machine speed and moisture content of 7.17% gives the best ratio of coarse to medium and fine of pulverized leaves, the machine can be used to produce moringa tea and moringa powder safely not using the local burr mill. Sieves of different grain sizes can be included in the machine and instrumented. The findings of this study regarding pulverizing mechanisms can also be applied to other herbs and leaves.
