Determination of selected engineering properties of cashew nut (Anacardium Occidentale) related to the design of cashew nut processing equipments

Cashew plant is a tree in the family Anacardiaceous. Cashew with botanical name Anacardium occidentale is extensively cultivated in the tropics mainly for its apples and nuts. This study aims at investigating the interactions of physical properties of the cashew nuts and its moisture content. The size and shape were described in relation to its surface area and sphericity, geometric mean diameter and arithmetic mean diameter. They were characterized using established procedure. Density was described on the basis of its true and bulk density which resulted to the porosity of the nuts. They were determined with reference using water displacement method. The frictional characteristics which are angle of repose and coefficient of friction were determined on three different structural surfaces plastic, metal and plywood on an inclined plane. Result obtained revealed that the mean value for the nuts major diameter, intermediate diameter, minor diameter, arithmetic mean diameter, geometric mean diameter, sphericity, surface area, mass, volume, true density, bulk density and porosity were 31.58±0.75 mm,  24.25±0.40 mm,  17.23±0.55 mm, 24.35±0.51 mm, 23.63±0.51 mm, 0.75±0.01 mm, 1754.20±75.14 mm2, 7.75±0.72 g, 7.65±0.52 cm3,  1.01±0.03 g/cm3,  0.58±0.03 g/cm3 and 42.53±0.04 % respectively at a moisture content ranging between 5 % to 8 % wet basis. The mean value for coefficient of friction for wood, plastic and metal structural surface was 0.068±0.01, 0.102±0.033 and 0.100±0.037 respectively at a moisture content ranging between 5 % to 8 % wet basis. The mean value for angle of repose for metal, plastic and plywood structural surface were 31.5±1.73°, 25.5±1.29° and 26.25±4.35° respectively. The effect of moisture content on the physical properties considered was significant, the results were expressed graphically.