Physical and mechanical properties of rapeseed at different moisture content

Physical and mechanical properties of three common varieties of rapeseed have been evaluated as a function of seed moisture content varying from 8.3 to 25.9%, from 7.7 to 27.4%, and from 7.3 to 26.4% (d.b.) for cv. Capitol, Jetneuf and Samurai, respectively. Increasing Moisture content was found to increase the length, diameter, geometric mean diameter, sphericity, seed volume, surface area, thousand grain weight, porosity, angle of repose and terminal velocity, and static friction coefficient on six structural surfaces, while decreasing bulk density, true density and rupture strength. Among the varieties, Capitol had the hi-hest values of geometric properties, at all moisture contents studied. An increase of sphericity with moisture content was observed. The maximum values of seed volume and Surface area among the varieties were obtained for Capitol seeds. Jetneuf seed had the highest porosity which increased with increase in moisture content. While thousand seed weight, angle of repose and terminal velocity increased as the moisture contents increased for all three varieties, bulk density, true density and rupture Force decreased as the moisture contents increased for all three varieties. At all moisture contents, rubber showed the highest friction coefficient, followed by plywood, then galvanized iron, glass, aluminium, and finally stainless steel. Capitol variety had the highest friction on all frictional surfaces at all moisture levels.