Moisture dependent physical properties of cardamom(Elettaria Cardamomum M.) seed

Abstract

Design of unit operations for mechanical and pneumatic cleaning, transportation (conveying), processing and storage of cardamom seeds are dependent on moisture content. Some of moisture dependent physical properties of cardamom seeds were studied at moisture contents 9.9%, 13.57%, 18.41%, and 23.29% wet basis (w.b.) The length, width, thickness, geometric mean diameter, thousand seed mass, and sphericity increased from 17.01 to 17.30mm, 5.68 to 6.57 mm, 5.02 to 5.35 mm, 7.86 to 8.47 mm, 120.83 to 165.60 g, and 0.46 to 0.49, respectively, with the increase in the moisture content from 9.9 to 23.29% w.b. As the moisture content increased from 9.9 to 23.29% the bulk density, true density, and porosity decreased from 408.2 to 358.90 kg/m³, 926.57 to787.19 kg/m³, and 55.94 to 54.41%, respectively. The angle of repose increased from 72.16^o at 9.9% to 73.80^o at 23.29% moisture content. Whereas, the static coefficient of friction increased with the increase in moisture content from 9.9 to 23.29% on three different surfaces. The highest static coefficient of friction was recorded when cardamom seed against plywood (0.47 to 0.56), and lowest static coefficient of friction against mild steel (0.41 to 0.50). The static coefficient of friction between cardamom seeds and galvanized iron surface increased from 0.44 to 0.53 within the studied moisture content range.