SOME ENGINEERING PROPERTIES OF THREE VARIETIES OF GROUNDNUT PODS AND KERNELS

Some engineering design related physical and mechanical properties of three varieties namely; Manipintar, Local I and Local II of groundnut pods and kernels were determined. This is of prime importance in the design, handling, processing and storage, separation and packaging systems of groundnut. In the study some engineering properties such as dimensions, geometric mean diameter (GMD), sphericity, surface area, bulk density, true density, porosity, volume, Mass, 1000- unit mass, angle of repose, static coefficient of friction on various surfaces and rupture force in 3 axes, were determined at 4.76, 4.04, 4.24 % and 6.29, 6.78, 6.61 % moisture contents dry basis for the three groundnut pods and kernels varieties, respectively. Bulk densities of pods and kernels were 0.27, 0.29 and 0.27 g/cm3, the corresponding true densities were 0.53, 0.53 and 0.38 g/cm3 and the corresponding porosities were 47.11, 43 and 28.4% for Manipintar, Local I and Local II respectively for the pods. The mean values of rupture force for groundnut pods of Manipintar through length, width and thickness were 1.19 N/mm, 3.99 N/mm and 5.25 N/mm respectively while that of Local I were 0.84 N/mm, 4.63 N/mm, and 6.50 N/mm respectively. Similarly, Local II has mean values of rupture force as 1.30 N/mm, 4.23 N/mm and 4.9 N/mm through length, width and thickness respectively. Statistical analysis of variance (ANOVA) was carried out to compare the mean values of the physical properties of the three varieties of groundnuts. It shows there was no significant difference at 5 % probability level between their means for groundnut pods. However, for the kernels, the length, width, thickness, GMD, and sphericity all show significant differences at 5% probability level.