Assessment of Physical and Thermal Properties of Velvet Bean (Mucuna pruriens) as Potentials for Development of Processing Machines

Abstract

The engineering properties of food materials have helped design, develop, and select suitable equipment for preservation, processing, packaging, and storage of food material, including velvet bean, an underutilised legume. Therefore, this research work is aimed at assessing the influence of moisture variation on some engineering properties of velvet beans. The velvet bean seed used was conditioned to moisture content ranging between 8.12 and 28.21 % to determine some selected physical properties. The thermal properties were determined using a KD2-Pro thermal analyser. The physical properties results indicated that the arithmetic mean, geometric mean, volume, and surface area increased with varying moisture content while there was a decrease in the sphericity and aspect ratio. Thermal conductivity, thermal diffusivity, and specific heat capacity ranged from 0.18 to 0.65 W/mK, 1.2×10-7 to 3.1×10-7 m2/s and 1.57 to 2.16 kJ/kgK, respectively. The physical and thermal properties of the seeds were measured and their respective high correlation coefficients indicate that they can be used to simulate these parameters within the moisture domain investigated. The physical and thermal properties of velvet bean differ significantly with moisture contents. The information obtained on some engineering properties of velvet bean seeds could help design processing machinery and optimise milling operations.