Extraction optimization of pectin from cocoa pod husks (Theobroma cacao L.) with ascorbic acid using response surface methodology

Abstract

Cocoa husks were used as the source for the pectin extraction by sugar acid treatment. A full factorial design was applied to screen the independent variables influencing the yield and uronic acid content. Followed by response surface methodology (RSM) was conducted using central composite design to optimize the extraction conditions. The optimized extraction condition was denoted as pH 2.5/95 °C/45 min. The yield and the uronic acid content of the extracted pectin was determined as 4.2 ± 0.12% and 74.5 ± 0.3% respectively. The extracted pectin was proved to be low methoxy pectin (LM pectin) with an 8.1% degree of esterification (DE). The pectin solutions showed shear thinning behaviour which was explicated by Williamson model. This work promotes environmentally friendly technology for pectin isolation.