Valorisation of fruit by-products: Production characterization of pectins from fruit peels

The aim of the study is to determine the physical, chemical, structural and thermal properties of the pectins obtained from melon rinds, kiwifruit and pomeganate peels and compared with the pectins obtained from apple and orange peel used in the commercial pectin production process. Pectins extractions from these wastes were performed with citric acid, at 80 °C and 60 min. All pectins, extracted, were found to be high methoxyl pectines. The water holding capacity of the melon rind, kiwifruit and pomegranate peels pectins were lower than the orange and apple peel pectins while the thermal stability of the kiwifruit peel pectin was close to the apple and orange peel pectins. The morphological structures of the extracted pectins showed that they had micro-fractures and hollow openings. The crystallinity of the melon rinds, kiwifruit and pomegranate peel pectins were smilar to orange peel pectin. The result of this study showed that the kiwifruit peel had advantages in terms of commercial pectin production due to its high pectin yield, water holding capacity, esterification degree and thermal stability.