Optimization of condition for pectin extraction from pomelo peel using response surface methodology

Abstract

The objective of this study was to optimize extraction condition of pectin from the pomelo peel based on the ultrasound-assisted extraction method using response surface methodology. The effect of four independent variables: solid/liquid ratio (1/30, 1/40, 1/50 g/mL), pH values of citric acid (pH 1.5 - 2.5), sonication time (30 - 50 min) and extraction temperature (60 - 80oC) on the yield of pectin extracted from Da Xanh pomelo pomace was analyzed using Box-Behnken design. The high coefficient of determination value (R2 = 0.9299) indicated that the experimental data were fitted to a second order polynomial equation using multiple regression analysis. The model was highly significant because the model F-value was 11.37 with low p-value (p < 0.0001). Therefore, the model could be employed to optimize the extraction process. Optimal experimental extraction condition for the highest pectin yield from pomelo peel (12.4%) were obtained with the solid/liquid ratio of 1/49.5 g/mL, pH of citric acid of 1.5, sonication time of 47 min and temperature of 78oC. The results obtained from validation experiments were consistent with the predicted data.

Keywords

• Pectin
• pomelo peel
• response surface methodology
• ultrasound-assisted extraction