Optimization of Supercritical Carbon Dioxide and Co-solvent Ethanol Extraction of Wasted Peanut Skin Using Response Surface Methodology

Peanut skin is a waste of peanut industries especially peanut butter industries. Peanut skin contain high antioxidant and high nutritional values. The objective of this study was to optimize the effect of parameters to obtain high extract yield and high antioxidant activity by using supercritical carbon dioxide and co-solvent ethanol. A Box-Behnken design (BBD) was used to optimize the extraction process at the condition temperature (40, 55 and 70 ºC), rate of co-solvent ethanol (2.5, 5, and 7.5 % Vethanol/Vtotal), and extraction pressure (10, 20 and 30 MPa). The extraction time was 3 hours. The optimum condition to obtain yield of extraction and antioxidant activity 22.05 MPa, 62.76 °C and 6.03 %(V ethanol /V solvent ) with 15.404 % yield extract and 94.040 % antioxidant activity.