Optimization of Mechanical Expression of Castor Seeds Oil (Ricinus communis) using Response Surface Methodology

  • J. O. Olaoye Department of Agricultural and Biosystems Engineering, University of Ilorin, P. M. B. 1515, Ilorin 240001, Kwara State, Nigeria.
  • R. A. Busari Food, Agricultural and Bio-Engineering Department, Kwara State University, Malete, Kwara State, Nigeria


The effect of the processing parameters of Castor seed on its oil yield was investigated. The castor seeds were passed through drying, crushing and separation into seeds and shells. These processing conditions were further succeeded by seed roasting and subsequent mechanical expression of the roasted nut by means of screw press in the course of its preparation for oil expression. Seed samples were conditioned by adding calculated amount of distilled water to obtain different moisture levels from the initial moisture content of the seeds. Samples were roasted at the temperatures of 83.18, 90.00, 100.00, 110.00 and 116.82°C, over periods of 6.59, 10.00, 15.00, 20.00 and 23.41min, seed moisture content of 6.32, 7.00, 8.00, 9.00 and 9.68 % wb, respectively and the oil was expressed using a screw roaster-expeller. Optimization of the oil expression process was achieved by applying Central Composite Rotatable Design of Response Surface Methodology. The optimal conditions for oil yield within the experimental range of the studied variables were 7%, 110°C and 20 min; moisture content, roasting temperature and roasting duration respectively. These values of the optimum process conditions were used to predict optimum value of oil yield to be 25.77%. A second-order model was obtained to predict oil yield as a function of moisture content, heating temperature and duration. Thus the result from this research work has established the optimal conditions for mechanical extraction of oil from castor seed. Closed agreement between experimental and predicted yield was obtained.

Dec 1, 2017
How to Cite
OLAOYE, J. O.; BUSARI, R. A.. Optimization of Mechanical Expression of Castor Seeds Oil (Ricinus communis) using Response Surface Methodology. Arid Zone Journal of Engineering, Technology and Environment, [S.l.], v. 13, n. 6, p. 878-887, dec. 2017. ISSN 2545-5818. Available at: <http://azojete.com.ng/index.php/azojete/article/view/302>. Date accessed: 22 apr. 2018.