Some Moisture Dependent Physical Properties of Baobab Seeds (Adansonia digitata L.)

Abstract

Baobab seed is a good source of protein and oil, but its processing and handling has not been mechanized. Therefore, this study determines the moisture dependent physical properties of baobab seeds that can be useful for development and performance of baobab seed processing and handling machines within
moisture level range of 8.38 to 52.26% dry basis (d.b). The properties (Major diameter, intermediate diameter and minor diameter, seed sphericity, bulk density, true density, porosity, geometric mean diameter, seed surface area and seed static coefficient of friction on different surfaces) were determined following ASAE 2005 Standard. The major diameter (D1), intermediate diameter (D2) and minor diameter (D3) of seed increased from 11.65 to 14.26mm, 9.43 to 11.38mm and 7.33 to 11.10mm, respectively with increased in moisture content levels from 8.38 to 52.26% (d.b). Seed sphericity decreased linearly from 80 to 78% as moisture content levels increases, while bulk density, true density and porosity increases from 667.04 to 1128.07kg/m3, 1196.79 to 1761.49 kg/cm3 and 36.09 to 44.66%, respectively as moisture content levels increases. Similarly, geometric mean diameter of the seed and seed surface area increases from 9.3 to 11.10 mm and 236.93 to 335.17mm2, respectively with increased in moisture content levels. Also seed static coefficient of friction on different surfaces increased in the order of mild steel plate (0.404 to 0.507), galvanized steel plate (0.502 to 0.525) and stainless steel plate (0.598 to 0.638) as moisture content levels increases.