Rice bran oil (RBO) extraction with ethanol using maceration method accompanied by stirring
has been optimized using response surface methodology (RSM) based on central composite design (CCD).
Experiments were conducted to investigate the influence of extraction time, ethanol concentration, and
ethanol volume on the oil yield, g-oryzanol, and vitamin E of RBO as the response. The experiment
consisted of twenty units including six replicates of the center points. The data were analyzed using Design�Expert 10 software to develop and evaluate models and to plot the response curve as 3D surfaces. The result
showed that the maximum of the oil yield, g-oryzanol, and vitamin E of RBO was achieved under the optimum conditions of x1 = 5.30 h, x2 = 89.21% and x3 = 686.66 mL (50 g rice bran), respectively. Maximum of the response under these conditions was 14.47%, 783.65 mg.L�1, and 127.01 mg.L�1, respectively. This study has resulted in the development of a model for RBO extraction using ethanol as solvent, it is feasible to be applied to the RBO industry with an efficient process, as well as an implementation of the “green” solvent concept.