Development and Evaluation of a Combined Castor Seed Roaster-Oil Expeller

Abstract

This study evaluated optimal process parameters for mechanical oil expression from castor seeds after designing a castor seed roaster-expeller. The effect of input variables (Moisture Content at 6, 7, 8, 9 and 10% db; Roasting Temperature at 80, 90, 100,110 and 120oC and Applied Pressure at 15, 20, 25, 30 and 35 MPa) on the oil yield, expression efficiency, expression loss and energy used were determined using Central Composite Design in Response Surface Methodology for the optimization and modelling. Analysis of Variance was employed to determine the level of significance (P≤ 0.05). The optimum expression efficiency, expression loss and minimum energy used were 72.86%, 0.63% and 584.19 Watts obtained at experimental conditions of 15.00 MPa applied pressure, 6% moisture content and 85.52°C heating temperature respectively. The R2 values of the developed models ranged from 0.813 to 0.982 at 95% confidence level. The developed combined castor seed roaster-oil expeller was found to be efficient and developed models showed adequate prediction with good relationships between dependent and independent variables. Keywords: castor seed, oil extraction, modeling, optimization DOI: 10.7176/ISDE/11-1-07 Publication date: January 31st 2020