Journal of Innovative Agriculture, Volume 3, Issue 4 : 1-10
Research Article

OPEN ACCESS | Published on : 29-Dec-2016

Construction of dehulling machine for improved coffee processing

  • Adeleke S A
  • Cocoa Research Institute of Nigeria, P.M.B 5244, Ibadan.
  • Ogunjobi MAK
  • Cocoa Research Institute of Nigeria, P.M.B 5244, Ibadan.


A machine was fabricated for dehulling wet-processed coffee using local materials. It was evaluated at different drum and fan speeds using parchment coffee at 10.7 w.b. moisture content. The results obtained indicated that the dehulling efficiency, bean damage and cleaning efficiency increased as the drum and fan speeds increased between 800 – 1400rpm and 1400 – 1900rpm respectively. However, there was no significant difference in dehulling efficiency and bean damage at these speeds (0.05 sig.), but the cleaning efficiency increased significantly at higher fan speeds. The highest average dehulling efficiency, cleaning efficiency and bean damage were respectively 97.59, 93.30 and 6.17%. High dehulling and cleaning efficiencies and low bean damage obtained indicate that the machine is very appropriate to handle coffee processing. Considering the reasonable performance achieved at wide range of the machine operating conditions, this work has a good prospect for commercial coffee production.


Parchment coffee, dehulling efficiency, cleaning efficiency, bean damage, Nigeria


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