Irvingia gabonensis and Irvingia wombolu are species of bush mango commonly found in
Africa whose kernel are processed into soup. Literature generally abounds on the
nutritional composition of the fruits and kernel but there is dearth of information on the
engineering properties which are very important in the design of processing equipment
and machines. This study was designed to investigate the influence of moisture on some
engineering properties of seeds and kernels of I. gabonensis and I. wombolu.
Irvingia gabonensis sourced from Oyo, Ogun, Osun and Irvingia wombolu sourced from
Edo, Ondo and Imo states, Nigeria were used for the study. Based on moisture content at
harvest and storage, their seeds were conditioned to moisture content of 10.0%, 20.0%,
30.0%, 40.0% and 50.0% and kernel to 2.2%, 3.7% and 5.3% (dry basis) using ASABE
method.Properties studied include dimension, sphericity, true and bulk densities, porosity
and angle of repose on commonly used material such as plywood, glass and steel for seed
and kernel. Deformation, rupture force, failure stress, stiffness and Young’s moduli for
seed were determined. Specific heat, thermal conductivity and diffussivity of kernel were
studied. All properties were evaluated using ASABE standards and data analysed using
ANOVA at p = 0.05.
Kernel length, width, thickness and sphericity increased respectively from 25.9 to 30.4
mm, 15.7 to 19.2 mm, 3.5 to 4.3 mm and 43.3 to 44.6% with increase in moisture content.
Length and width of seed decreased from 53.5 to 34.7 mm and 38.4 to 30.3 mm
respectively with increase in moisture content while, thickness and sphericity increased
from 3.5 to 4.2 mm and 66.7 to 78.0% respectively, indicating that seeds swell only in the
lateral direction. Sphericity of seed was high indicating tendency to roll easily while low
sphericity of kernel indicates sliding on structural surfaces. True density increased from
825.6 to 1216.4 kgm-3 and 697.7 to 1092.0 kgm-3
for seed, and kernel respectively. Their
densities appear close to that of water hence may be difficult separating them using water.
Angle of repose increased from 30.4 to 52.9o and 18.9 to 29.0o
for seed and kernel
respectively and was significantly affected by moisture content and species. Based on
existing design, hopper and inclined discharge chute can be used for seed and flat bed for
kernel. Deformation and Young’s modulus increased linearly from 1.4 to 3.9 mm and 5978.0 to 26098.0 Nmm-2
respectively for seed and were significantly affected by
moisture and species. Specific heat and thermal conductivity of the two species increased
with moisture and those of I. wombolu (982.8 JkgK-1
, 0.2 Wm-1K
) were significantly
higher than I. gabonensis (795.9 JkgK-1
, 0.1 Wm-1K
) kernel. Thermal diffussivity also
increased with moisture content and was significantly higher in I. wombolu than
I.gabonensis; hence I. wombolu kernels will dry faster.
Mechanical properties of the seeds evaluated at the selected moisture content showed that
more energy would be required in cracking of Irvingiawombolu during kernel extraction
than the same quantity of Irvingia gabonensis at the same processing condition.
The Public Access, L (2021). INFLUENCE OF MOISTURE ON SOME ENGINEERING PROPERTIES OF BUSH MANGO SPECIES [Irvingia gabonensis AND Irvingia wombolu (HOOK, F.)] SEED AND KERNEL. Afribary.com: Retrieved April 14, 2021, from https://afribary.com/works/influence-of-moisture-on-some-engineering-properties-of-bush-mango-species-irvingia-gabonensis-and-irvingia-wombolu-hook-f-seed-and-kernel-1
Library, The Public Access. "INFLUENCE OF MOISTURE ON SOME ENGINEERING PROPERTIES OF BUSH MANGO SPECIES [Irvingia gabonensis AND Irvingia wombolu (HOOK, F.)] SEED AND KERNEL" Afribary.com. Afribary.com, 01 Apr. 2021, https://afribary.com/works/influence-of-moisture-on-some-engineering-properties-of-bush-mango-species-irvingia-gabonensis-and-irvingia-wombolu-hook-f-seed-and-kernel-1 . Accessed 14 Apr. 2021.
Library, The Public Access. "INFLUENCE OF MOISTURE ON SOME ENGINEERING PROPERTIES OF BUSH MANGO SPECIES [Irvingia gabonensis AND Irvingia wombolu (HOOK, F.)] SEED AND KERNEL". Afribary.com, Afribary.com, 01 Apr. 2021. Web. 14 Apr. 2021. < https://afribary.com/works/influence-of-moisture-on-some-engineering-properties-of-bush-mango-species-irvingia-gabonensis-and-irvingia-wombolu-hook-f-seed-and-kernel-1 >.
Library, The Public Access. "INFLUENCE OF MOISTURE ON SOME ENGINEERING PROPERTIES OF BUSH MANGO SPECIES [Irvingia gabonensis AND Irvingia wombolu (HOOK, F.)] SEED AND KERNEL" Afribary.com (2021). Accessed April 14, 2021. https://afribary.com/works/influence-of-moisture-on-some-engineering-properties-of-bush-mango-species-irvingia-gabonensis-and-irvingia-wombolu-hook-f-seed-and-kernel-1