Application of combined Box-Behnken design with response surface methodology and desirability function in optimizing pectin extraction from fruit peels.

Background: This study aimed to extract pectin from various fruit peels, namely apple, orange, green citron, and pomegranate, and to evaluate the effects of various experimental conditions. The extraction was conducted at temperatures of 50-90 °C, with a solid-liquid ratio of 0.03-0.08 g/mL, for 120-180 min. The Box-Behnken design was applied in a three-level and four-factor factorial approach, including 29 experiments for each extraction, with varying conditions. The interaction effects were investigated. Each experiment's conditions were optimized.

Results: The percentage yield varied (11.70-37.37%). The maximum yield was found in apples, whereas the lowest was in pomegranates.

Conclusion: Under optimized experimental conditions,high-quality pectin was extracted from pomegranate, orange, green citron, and apple peel waste. The extract was considered to be high methyl ester pectin with a degree of esterification greater than 50% and with an Anhydrouronic acid (AUA) content greater than 65%. The peel pectin that was studied could therefore be a food additive with numerous uses. The procedure developed here reuses waste resources effectively and contributes to a novel concept for exploring natural assets for use in food and pharmaceutical applications. © 2023 Society of Chemical Industry.