Odour active compounds determined in the headspace of yellow and black plum wines (Prunus domestica L.)

Abstract

Odour active compounds (OACs) from the headspace of yellow and black plum wines (Prunus domestica L.) were analysed using gas chromatography-mass spectrometry-olfactometry (GC-MS-O). Olfactometry was conducted using aroma extract dilution assay, through varying split ratios during injection. A total of 18 OACs were determined in the wine headspace including esters, ketones, sulfur containing compounds, alcohols, a terpene, and phenolic compounds. Thirteen of volatile compounds differed significantly (p < 0.05) in concentration between plum wines. Unique OACs were also detected within the headspace that distinguished the wines, where 4-ethyl guaiacol was only detected in the yellow plum wine and diacetyl was only detected within the black plum wines. The remaining nine OACs were not significantly different from each other, suggesting their ubiquity in the plum wines. High flavour dilution (FD) values were determined for ethyl isobutyrate, ethyl 2-methyl butyrate, β-damascenone, and ethyl cinnamate. All compounds detected in the plum wines have been previously reported in grape wine and demonstrated the commonality of volatile constituents between plum and grape wine. However, the very high concentration of β-damascenone may strongly contribute to the overall aroma of the plum wines.