Physical Properties of Moringa (Moringa oleifera) Seeds in relation to an Oil Expeller Design

Abstract

Physical properties are very important in the design and manufacturing of processing machines. In this research work, the physical properties of Moringa were determined as design parameters for the development of an oil expeller for the crop. The properties were: length, width, thickness, arithmetic and geometric diameters, surface area, sphericity, aspect ratio, moisture content, bulk and true densities, porosity, one thousand seed weight, angle of repose and coefficient of static friction. The average moisture content was found to be 7.31 % wet basis. The average seed length, width and thickness were found to be 8.45, 7.82 and 6.41 mm respectively. The average arithmetic and geometric mean diameters were 7.560 and 7.490 mm respectively. The average surface area was 177.19 mm2; while the mean sphericity and aspect ratio were 0.889 and 0.9257 respectively. The average true and bulk densities were 971 and 662 kgm^-3 respectively and the porosity was 68.18%. The mean angle of repose was 21.44o. The average static coefficient of friction on six different surfaces viz glass, stainless steel, mild steel, galvanized steel, rubber and plywood was found to be 1.027, 1.111, 1.376, 1.234, 2.199 and 1.607 respectively. It was found to be highest on rubber and lowest on glass. These parameters would serve as inputs for the efficient design of the oil expeller for Moringa seeds.

Keywords: Moringa, Physical Properties, Oil and Oil Expeller.