Study of the aroma compounds of rose apple (<Emphasis Type="Italic">Syzygium jambos</Emphasis> Alston) fruit from Brazil

Volatiles of the headspace and total aqueous extract from the rose apple fruit were investigated by gas chromatography (GC)–flame ionization detection, GC–mass spectrometry and GC–olfactometry/aroma extract dilution analysis O/AEDA). The headspace fraction was rich in low boiling compounds, while medium and high volatility components predominated in the total aqueous extract. GC–O/AEDA revealed that hexanal, 3-penten-2-one, hexanol, (Z)-3-hexen-1-ol, linalool, isovaleric acid, benzyl alcohol, 2-phenylethylalcohol and (E)-cinnamaldehyde were potent odorants contributing to the headspace aroma. Thus, they might be related to the first odour impression of the fruit. Other potent volatiles, such as caproic and phenylacetic acids, methyl-(E)-cinnamate and (E)-cinnamyl alcohol were identified in the total aqueous extract, only. These results indicated that some volatiles, with medium and high boiling points, might also contribute to the overall rose apple flavour. Besides them, volatiles with lower odour potency, such as 7-octen-4-ol, acetic acid, 2-octen-1-ol and cinnamic acid, could have some additional effect for the overall fruit aroma.