International Journal of Food Science and Nutrition

Authors
Wickramasinghe U L, Marapana R A U J, Anuradha P A V

Abstract
Passion fruit contains 50–55 g of peel for every 100 g of fresh fruit, and this peel is discarded as waste in the production of fruit juice and other processed fruits. The utilization of waste passion fruit peel in pectin extraction is studied and the main objective of this study is to compare the purple passion fruit variety (Passiflora edulis) against the yellow variety (Passiflora edulis f. flavicarpa). Also, pectin was extracted, isolated, and compared by characterization under two pretreatment conditions: blanched and non-blanched, and the physio-chemical properties were compared to those of commercial pectin. The results indicate that blanching, as a pretreatment, plays a significant role. Thus, the blanched samples have given favorably higher values than non-blanched samples in both varieties in terms of tested characteristics and yields. The extraction was done at 60oC of temperature, 20 kHz of frequency, and under four power intensities; 150, 370, 660, and 890W. Optimum results were obtained at 660W and it was noticed that the rising power intensity negatively affects DE, equivalent weight, methoxyl content, and anhydrouronic acid content. The yield, DE, equivalent weight, methoxyl content (per 100g of pectin) and anhydrouronic acid content (per 100g of pectin) at 660w from blanched purple passion fruit peel are 13.80%, 82.99%, 1152.68, 8.26g, 61.95% respectively and from blanched yellow passion fruit peel are 13.38%, 78.61%, 696.51, 7.05g, 65.38% respectively. Purple passion fruit peel is a better source of pectin than the yellow variety under the studied physio-chemical properties and is a good match to commercial citrus pectin, thus an effective utilization of fruit processing waste.