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Production of cocoyam is mainly carried out manually. Adequate knowledge of their engineering properties is a
prerequisite for the development of machinery for harvesting and processing of cocoyam. Some engineering
properties of cocoyam from two species of cocoyams, namely Colocasia exculenta (taro) and Xanthosoma
saggittifoluim (tannia) were compared. The properties investigated include tuber length, width, volume, angle of
repose, density, static coefficient of friction, force–deformation behaviour during compression, stiffness moduli and
tuber toughness. Xanthosoma sagittifolium was found to have length of 9.66 ± 4.65 cm, width of 4.24 ± 0.55 cm, and
thickness of 4.20 ± 0.73 cm; while Colacassia esculenta have length of 8.5 ± 3.30 cm, width 3.52 ± 0.33 cm and
thickness of 3.51 ± 0.34 cm. Xanthosoma sagittifolium and Colacassia esculenta was found to have an average
moisture content of 57.65 % and 58.91 % (wet basis)respectively. The average mass, volume and density of
Xanthosoma sagittifolium are 126.28 g, 123.75 cm3 and 1.02 g/cm3 respectively while the mass, volume and density of
Colacassia esculenta are 76.21 g, 75.42 cm3 and 1.01 g/cm3 respectively. The mean values of coefficient of static
friction was 0.31and 0.21 on wood, 0.31and 0.21 on glass, 0.22 and 0.20 on stainless and 0.25 and 0.21 on
galvanized iron surfaces for Xanthosoma sagittifolium and Colacassia esculenta respectively. The average values of
angle of repose of Xanthosoma sagittifolium and Colacassia esculenta were 14.05 and 11.99; compressive force was
1628.68 N and 1121.08 N; toughness of 11.02 Nm and 6.89 Nm; Young Modulus of 2365.0 N/mm2 and 11.98 N/mm2 respectively.