Development and performance tests of a melon (egusi) seed shelling machine

Abstract

Abstract: In order to solve the boredom involved in melon shelling operation which is one of the major factors militating against the large scale production, processing and the use of this important oil crop, a power-driven melon seed shelling machine was designed, constructed and tested. The machine consists of a feed hopper, a shelling unit, a delivery chute, a power system and a tool frame. The shelling action was achieved by principle of a rotor that throws melon seeds against the shelling drum by centrifugal force and then the seeds were converged onto a spinning disc with vanes that provide impact force to remove the kernel from the shell.The results of the performance tests carried out showed that the machine shelling efficiency increased with the increase in moisture content and speed.  Maximum shelling efficiency percentage of 95% was obtained at the seed moisture content of 26.6% d.b and at 2190 rpm shelling speed. Percentage seed damage was found to decrease with the increase in seed moisture content. Machine capacity and throughput capacity were 192 kg/h and 796 kg/h respectively.  The analysis of variance showed that moisture content and machine shelling speed have significant effect on both shelling efficiency and percentage seed damage at 1% level. Regression models that could be used to express the relationship among the performance indices, moisture content and machine speed were established.

Keywords: melon, sheller, efficiency, seed damage, machine capacity, machine speed, seed moisture content.