Optimization of pectin extraction from cacao pods using microwave assisted extraction (MAE) as a sustainable method for on-farm waste utilization

Cacao pods are the main waste of cacao on-farm processing that contains pectin. Generally, it is utilized for culinary purposes due to its gel-forming characteristic. Cacao pod pectin extraction was conducted by the MAE method using citric acid as a solvent. This study aims to determine the most appropriate optimum conditions from determined parameters of solvent pH and solvent-to-substrate (S/S) ratio using Response Surface Methodology (RSM) with yield as a response. There are two phases in this research, namely the preparation of cacao pod powder and pectin extraction from cacao pod powder with variations in the pH and S/S ratio of each 1.0; 1.5; 2.0 and 15:1; 20:1; 25:1 (v/w). This research confirmed that optimal conditions were reached at S/S ratio 21.57:1 (v/w) and pH 2.0 with a yield of 3.51%. Then, it was evaluated by comparing to commercial pectin for its degree of esterification (DE) and moisture content (MC). This experiment concluded that MAE technique is a potential method for sustainable pectin extraction. It can be applied on a larger scale due to shorter extraction time with fewer requirements for solvent and industrially more acceptable regarding the environmentally friendly.