Effect of extraction conditions on the quality characteristics of pectin from passion fruit peel ( Passiflora edulis f. flavicarpa L.)

Abstract

Passion fruit ( Passiflora edulis f. flavicarpa L.) yellow variety is composed of 50–55 g peel per 100 g of fresh fruit which is discarded as waste during processing. Utilization of passion fruit peel for pectin extraction was studied. Passion fruit peel obtained after juice extraction was blanched in boiling water for 5 min, dehydrated in a cross flow hot air drier at 60 ± 1 °C to a moisture content of 4 g/100 g of dried peel. The dehydrated passion fruit peel was used for extraction experiments of pectin. The effect of pH, peel to extractant ratio, and number of extractions, extraction time and temperature on the yield and quality characteristics of pectin were investigated. The optimized conditions for extraction of pectin from passion fruit peel yielded 14.8 g/100 g of dried peel. Pectin extracted from the dried peels had a methoxyl content of 9.6 g/100 g, galacturonic acid content of 88.2 g/100 g and jelly grade of 200. Extraction of pectin from dried peels of passion fruit may be considered for effective utilization of passion fruit processing waste.