50 mL of
acetic acid solution (30 ml of glacial acetic was made up to 500 mL
with distilled water) was added followed by 25 mL of Calcium
chloride solution (27.5 g of anhydrous Calcium chloride dissolved in
500 mL of distilled water) with stirring. The mixture was allowed to
stand for 1 h and boiled for 2 min. Pectin was precipitated as
Calcium pectate and filtered through a No. 4 Whatman paper. The
precipitate washed with hot distilled water till it is free from
chlorides. The filter paper containing the calcium pectate dried
overnight in a oven at 100 C. The filter paper was cooled in
a desiccator and weighed. Total pectic substance estimated as
calcium pectate in dried peels of passion fruit was considered as
100% pectin for calculating the recovery of pectin from peels during
extraction.