Optimisation of Kernels Preparation Conditions Involved in the Press Extraction of Shea ( Vitellaria paradoxa Gaertner F.) Butter

Abstract

In this study, different conditions of press extraction of shea butter were optimised. Response Surface Methodology (RSM) using the Doehlert experimental design has been employed in the optimisation. The independent variables considered were roasting time (0-60 min), roasting temperature (50-300°C), cooking time (0-300 min) and cooling time (0 -60 min). Four-second order polynomial models were generated. The models were well described the responses: extraction yield, acid value, peroxide value and Lovibond red colour of the process with satisfactory fits in terms of absolute average deviation and coefficient of determination. The optimum conditions were found to be 10-15 min roasting time, 160-225°C roasting temperature, 140-275 min cooking time and 30-40 min of cooling time. The optimum responses were 45.7% extraction yield, 19.3 acid value, 5.4 peroxide value and 1.6 Lovibond red colour. The statistical relation between the four independent variables and the process responses was well described.