SOME ENGINEERING PROPERTIES OF DRUMSTICK (MORINGA OLEIFERA) SEEDS

Abstract

Some engineering properties of drumstick seeds were determined following standard methods in the
literature. The results show that the mean values of 100 measurements for length, width, thickness and
mass of drumstick seeds at a moisture content of 4.64% (w.b) were: 10.96, 10.83, 10.24 mm and 0.35 g
for the nut and 7.44, 8.59, 8.29 mm and 0.26 g for the kernel. The kernel-nut ratio showed that the kernel
is 74% of the nut weight. Angle of repose and loose and bulk densities were: 46.8º, 212 kg/m³, 223.6
kg/m3 for the nut; and 42.5º, 518.1 kg/m3, 531.2 kg/m3 for the kernels respectively. Terminal velocities of
the nut, kernel and shell were: 8.39, 9.83 and 5.67 m/s respectively. Static coefficient of friction on mild
steel, glass, galvanized steel and formica surfaces were 0.69, 0.48, 0.49 and 0.37 for the nuts and 0.37,
0.42, 0.35 and 0.30 for kernels respectively. The rupture force was 54.47 N for the nut and 67.27 N for
the kernel. Hydration and swelling capacities were 0.25 g/kernel and 0.47 mL/kernel; while hydration and
swelling indices were 0.96 and 1.78 respectively. Minimum cooking time, water uptake ratio, cooked
weight, water absorbed and gruel loss were 37 mins., 0.74, 17.43 g/10 g, 7.43 g/10 g and 5.58% for
traditionally cooked samples and 20 mins., 0.62 g/g, 15.94 g/10 g, 5.94 g/10 g and 1.47% for the
microwave cooked samples.