Effect of Processing Parameters on the Quality of Passion Fruit (Passiflora edulis) Juice Concentrate

Abstract

The volatile compounds of passion fruit juice were isolated by Likens Nikerson distillating extraction method, then analyzed and identified by gas chromatographic method and GC MS method. With 41 esters, 8 terpene compounds, 6 alcohols, 3 ketones, 2 acids, 1 aldehyde and 2 hydrocarbons. The juice seas first pasteurized at 75℃ for 40 sec, then depectinized at 50℃ for 30 min with Ultrazym-100 60 ppm and centrifuged at 13,000x g with a Sharples type centrifuge. The centrifuged juice was first recovered aroma in this experiment with 150 folds to the original juice, but its total yield is only 12.6%, then recycle concentrated in a single separator to raise solid content to 43° Brix as 2.7 folds from the original juice by a pilot scale Unipek-tin P15l-3S three-effect evaporator with aroma recovery system. The results indicate that a little higher in ”L” and ”b” values of color found in the reconstituted juice than that in the original juice. From these experiment results demonstrated, using the pilot scale three-effect evaporator at controlled condition for the clarified passion fruit juice could get 4 folds passion fruit juice concentrates. After three months stored at low temperature, the juice concentrate was cut back smith the recovered aroma. The quality of reconstituted juices are closed to the juices before concentration. Therefore, suing the pilot scale three-effect evaporator with aroma recovery system for passion fruit juice is worthy developing and applied in fruit juice industry.