Received: 03-03-2021 / Accepted: 10-05-2021
Passion fruitpeel accounts for a very high percentageof the total fruit weight. Therefore, taking advantage of this by-product source to extract pectin will both create valuable products for application in the food industry and contribute to solving environmental problems. This study aimed to find the optimal conditions for extracting pectin from the peelsof purple passion fruit and to evaluate the effect of extraction conditions on the degree of esterification of pectin. Using a central composite design (CCD) with a response surface methodology (RSM), the results showedthat the generated quadratic model adequately explained the data variation and significantly represented the actual relationship between the independent variables and the responses. This study also found the optimal conditions to extract pectin from passion fruit peelsas follows: citric axit concentration of 8.00%, temperature of 82.14C and extraction time of 81.07 min for the highest yield of pectin (24.42%). Thepectin extracted under the optimum conditions had the followingphysicochemical properties: equivalent weight (EW) of 586.92± 17.55; degree of esterification (DE) of 38.76± 1.52 %; methoxyl index (MI) of 3.94± 0.13 %; total anhydrouronic acid content (AUA) of 76.58± 1.19 %. Thesecharacteristics are suitable for the purpose of edible film making, opening up a potential application for this pectin. In addition, the extraction conditions had a marked effect on the degree of esterification of pectin from purple passion fruit peel.