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Psidium guajava L. - syn.Psidium pomiferum D.C., Psidium pyriferum L. - Myrtaceae - common guava, Echte Guave
Evergreen shrub or small tree native to the Caribbean, Central America and South America, widely cultivated for the fruit in tropical and subtropical regions around the world. „Various cultivars have white, pink, or red flesh, and a few also feature red (instead of green) skin.“
http://en.wikipedia.org/wiki/Psidium_guajava
The most important (FD factors) aroma compounds present in fresh, pink-fleshed Colombian guavas (Psidium guajava, L.), variety regional rojo, were 4-methoxy-2,5-dimethyl-3(2H)-furanone, 4-hydroxy-2,5-dimethyl-3(2H)-furanone, 3-sulfanylhexyl acetate, and 3-sulfanyl-1-hexanol followed by 3-hydroxy-4,5-dimethyl-2(5H)-furanone, (Z)-3-hexenal, trans-4,5-epoxy-(E)-2-decenal, cinnamyl alcohol, ethyl butanoate, hexanal, methional, and cinnamyl acetate. Enantioselective GC revealed an enantiomeric distribution close to the racemate in 3-sulfanylhexyl acetate as well as in 3-sulfanyl-1-hexanol.
[Characterization of the aroma-active compounds in pink guava (Psidium guajava, L.) by application of the aroma extract dilution analysis., Steinhaus, M., Sinuco, D., Polster, J., Osorio, C., Schieberle, P., Journal of agricultural and food chemistry, 56(11), 2008, 4120-4127]
3-sulfanylhexyl acetate (tropical fruity, black currant-like)
„Seventeen aroma-active volatiles, previously identified with high flavor dilution factors in fresh, pink Colombian guavas (Psidium guajava L.), were quantified by stable isotope dilution assays. On the basis of the quantitative data and odor thresholds in water, odor activity values (OAV; ratio of concentration to odor threshold) were calculated. High OAVs were determined for the green, grassy smelling (Z)-3-hexenal and the grapefruit-like smelling 3-sulfanyl-1-hexanol followed by 3-sulfanylhexyl acetate (black currant-like), hexanal (green, grassy), ethyl butanoate (fruity), acetaldehyde (fresh, pungent), trans-4,5-epoxy-(E)-2-decenal (metallic), 4-hydroxy-2,5-dimethyl-3(2H)-furanone (caramel, sweet), cinnamyl alcohol (floral), methyl (2S,3S)-2-hydroxy-3-methylpentanoate (fruity), cinnamyl acetate (floral), methional (cooked potato-like), and 3-hydroxy-4,5-dimethyl-2(5H)-furanone (seasoning-like). Studies on the time course of odorant formation in guava puree or cubes, respectively, showed that (Z)-3-hexenal was hardly present in the intact fruits, but was formed very quickly during crushing. The aroma of fresh guava fruit cubes, which showed a very balanced aroma profile, was successfully mimicked in a reconstitute consisting of 13 odorants in their naturally occurring concentrations. Omission tests, in which single odorants were omitted from the entire aroma reconstitute, revealed (Z)-3-hexenal, 3-sulfanyl-1-hexanol, 4-hydroxy-2,5-dimethyl-3(2H)-furanone, 3-sulfanylhexyl acetate, hexanal, ethyl butanoate, cinnamyl acetate, and methional as the key aroma compounds of pink guavas.“
[Characterization of the key aroma compounds in pink guava (Psidium guajava L.) by means of aroma re-engineering experiments and omission tests. Steinhaus, M., Sinuco, D., Polster, J., Osorio, C., Schieberle, P., Journal of agricultural and food chemistry, Vol.57(7), 2009, 2882-2888]
„…numerous compounds are formed during guava ripening process, but only few of them are responsible for the characteristic fruit flavour… (Z)-3-hexenal, ethyl butanoate, 4-hydroxy-2,5-dimethyl-3(2H)-furanone, 3-sulphanyl-1-hexanol, and 3-sulphanylhexyl acetate were established as major odour-active compounds in guava at al ripening stages, but nevertheless their concentrations differed significantly depending on maturity… 3-sulphanylhexyl acetate and 3-sulphanyl-1-hexanol decreased with ripening, while the concentrations of aliphatic esters and furanones increased during this process“
[Changes in odour-active compounds of two varieties of Colombian guava (Psidium guajava L.) during ripening., Sinuco, D.C., Steinhaus, M., Schieberle, P., Osorio, C., European Food Research and Technology, 230(6), 2010, 859-864]
Psidium guajava as Psidium pumilum Vahl; Blanco, M., Flora de Filipinas, t.172 (1875)
http://plantgenera.org/species.php?id_species=844853