Hydrolytically-released volatile secondary metabolites from a juice sample of Vitis vinifera grape cvs Merlot and Cabernet Sauvignon

Abstract

The volatile components of a Merlot and a Cabernet Sauvignon juice, as well as the volatile compounds released by acid- or glycosidase enzyme hydrolysis of C18 reverse phase isolates of the juices, have been analysed. The categories of constituents (i.e. monoterpenes, benzenoid compounds, norisoprenoids, aliphatic and miscellaneous compounds) and the components observed within these categories were broadly similar to those previously reported for other varieties. The potent flavour compound, damascenone, was a major component of the acid hydrolysates of both juice samples. The damascenone precursor trans-megastigma-6,7-diene-3,5,9-triol was identified as a hydrolysis product of grape-derived C18 reverse phase isolates for the first time.