Process Conditions Governing Mechanical Expression of Shea Butter from Crushed Shea Kernel under Uni-Axial Compression

Abstract:

Mechanical expression of shea butter from shea kernel (Vitelaria paradoxa) was studied using a 4³ factorial experiment under a Randomized Complete Block Design. The mechanical expression rig comprised an instrumented pistoncylinder assembly in conjunction with a Universal Testing Machine (UTM). Shea butter was mechanically expressed through the perforated base of the press cage cylinder when crushed shea kernel was subjected to uniaxial compressive loading by the UTM. The process conditions were heating temperatures of 50, 70, 90 and 110 °C; applied pressures of 1.5, 2.9, 5.8 and 8.8 MPa and loading speeds of 2.50, 5.00, 7.50 and 10.00 mm min^-1. Heating of the crushed shea kernel samples prior to shea butter extraction was achieved by a temperaturecontrolled band heater enfolding the press cage cylinder. Results showed that a maximum oil yield of 35.10 %, a maximum oil recovery efficiency of 58.50 % and a minimum process loss of 2.83 % were obtained at a heating temperature of about 70 °C, an applied pressure of about 8.8 MPa and a loading speed of about 2.50 mm min^-1.

• Periodical: International Journal of Engineering Research in Africa (Volume 10)
• Pages: 37-48
• DOI: https://doi.org/10.4028/www.scientific.net/JERA.10.37
• Online since: July 2013
• Authors: A.M. Olaniyan, K. Oje
• Keywords: Oil Recovery Efficiency, Oil Yield, Process Conditions, Process Loss, Shea Butter, Shea Kernel

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