Vacuum headspace method in aroma research:: Flavor chemistry of yellow passion fruits

The volatile flavor components of yellow passion fruits have been isolated using four different isolation techniques. The most representative and typical extract was obtained by vacuum headspace sampling and subsequent liquid-liquid extraction of the aqueous phase. This vacuum headspace concentrate was prefractionated by medium-pressure adsorption chromatography on silica gel. Approximately 180 components were identified in the LC fractions of yellow passion fruit flavor for the first time. Of these compounds, 14 components have not previously been reported as naturally occurring flavor ingredients. Moreover, 47 sulfur-containing volatiles were identified in yellow passion fruits after enrichment by preparative multidimensional capillary gas chromatography; 35 of these components are reported to be present in the tropical fruit flavor for the first time, and 23 of these sulfur-bearing compounds have not been previously reported as constituents of food flavors and are therefore new natural components. In addition, the enantiomeric distributions of several chiral flavor substances were determined by enantioselective multidimensional gas chromatography.