Application of Response Surface Methodology in Optimization Condition of Anthocyanin Extraction Process of Cocoa Peel Waste with Microwave Assisted Extraction Method (MAE)

Abstract

Anthocyanins are present in high concentration in cocoa peels. A microwave-assisted extraction was used to extract the anthocyanins from cocoa peel by using aqueous ethanol solvent. Extraction process conditions such as particle size, material/solvent ratio (w/v), optimum extraction time, and microwave power in the extraction process will affect the obtained concentration of anthocyanin. The purpose of this study is to identify the relationship between each input variables and to develop predictive models used in optimizing the conditions of the anthocyanin extraction process. The Design Expert vs11 program with Response Surface Methodology (RSM) Box-Behnken Design was used for research and select process conditions from a combination of factors producing the optimal responses. Based on the Box-Behnken RSM Design, particle size, material/solvent ratio, extraction time, and microwave power in the extraction process are factors which mainly affect the response of produced anthocyanin concentration. Relationship between variables and the response of anthocyanin concentration was modeled by Y = 0.000178-4.17412E-07A + 0.012205B + 0.000022C + 7.75551R-08D + 0.000060AB – 2.96236E-08AC + 1.20818E-09AD – 0.001314BC – 0.000029BD + 1.84413E-07CD (A is particle size; B is the ratio of cocoa peel/ethanol; C is extraction time; and D is the power of microwave). The optimal response value of anthocyanin concentration is 1,435 mM, with the condition of the particle size at the extraction process of 60 mesh; the ratio of cocoa peel/ethanol of 0.0625 w/v; extraction time of 10 minutes; and the microwave of 450 watts.