Enzymatic hydrolysis of edible Passi¯ora fruit glycosides

The combined action of Hemicellulase REG 2 and sweet almond glucosidase containing b-d-glucopyranosidase, a-l-rhamno-pyranosidase, a-l-arabinopyranosidase and a-l-arabinfuranosidase activities allowed release of most of the volatile compounds bound as aglycones in edible Passi¯ora fruits. Great variability between the four species studied, P. edulis, P. edulis f falvicarpa, P. ligularis, P. molissima, was noticed. 2,5-Dimethyl-4-hydroxy-3-(2H)furanone (furaneol)was identi®ed for the ®rst time in bound form in purple and yellow passion fruit. Only geraniol was identi®ed as the aglycone in P. molissima. and no terpenol is present in the hydrolysate obtained from P. ligularis. Several terpene diols: 2,6-dimethyl-1,8-octanediol, (E)- and (Z)-2,6-dimethylocta-2,7- diene-1,6-diol, 2,6-dimethylocta-3,7-dien-2,6-diol and ,6-dimethylocta-1,7-dien-3,6-diol have been identi®ed in both purple and yellow passion fruit and small amounts of Z)-2,6-dimethylocta-2,7-diene-1,6-diol are present in P. molissima. a-Ionol derivatives oxygenated in position 3 seem to be characteristic of purple passion fruit whereas b-ionol compounds oxygenated in position 3 are the major norisoprenoids identi®ed as the aglycone in yellow passion fruit. The bound norisoprenoid content of P. ligularis and P. molissima is low. Important concentrations of bound aromatic alcohols are found in purple and yellow passion fruit whereas phe- nolics can be considered as characteristic of purple varieties.