Synthesis and characterization of edible films using high methoxyl pectin extracted from orange peel

Abstract This study aimed to examine the effectiveness of the extraction of pectin from orange peel waste using hydrochloric acid and citric acid and how they affect the quantity and quality of pectin, as well as the potential uses of the extracted pectin in edible film formulations. Both extraction procedures were used to extract orange peel samples at 80 °C for one hour. The results showed that using hydrochloric acid to extract pectin (HP) achieved slightly better results (15.15%) than using citric acid, CAP (14.44%). Chemical analysis showed that the two methods were quite different: the pectin from hydrochloric acid had more moisture (3.00%) with a higher equivalent weight of 806.45 mg/mol, while the pectin from citric acid had more ash (1.952%) and a lower equivalent weight of 769.23 mg/mol. Both extraction techniques maintained critical functional properties, and esterification values remained within market standards (51.85%). The extracted pectin was effectively used to make edible films, indicating its potential for other valuable applications. The edible films were characterized by mechanical properties, WVP, optical properties, SEM, FTIR, XRD, DPPH, and biodegradability. The citric acid edible films had the highest DPPH and tensile strength, the lowest elongation and WVP, and the highest degradability in soil. So, the citric acid extraction procedure was demonstrated to be environmentally friendly and lower environmental impact. This study provides valuable insights into producing pectin in an environmentally friendly manner for the food and packaging sectors.