title: Distribution and Organoleptic Impact of Ethyl 3-Hydroxybutanoate Enantiomers in Wine.
abstract: Enantiomers of ethyl 3-hydroxybutanoate were assayed in 87 commercial wines from various vintages and origins, using chiral gas chromatography (β-cyclodextrin). Generally, ethyl 3-hydroxybutanoate levels were higher in red than in white wines of the same age. The average S/R enantiomeric ratio of this compound in red wine was approximately 75:25 (± 13), with an average total concentration of ∼ 450 (± 150) μg/L. In red wines, R-form levels increased gradually during aging, but no variations were observed in S-form concentrations. To our knowledge, no previous research had determined the enantiomeric distribution of this compound in wine. The olfactory threshold of the S-form in dilute alcohol solution was 21 mg/L, one-third that of the R-form: 63 mg/L. The S- and R-forms had different aromatic nuances. The olfactory threshold of their mixture (85:15, m/m) was 14 mg/L, indicating a simple additive effect in this binary mixture. Furthermore, the concentrations found in red wines were considerably below the olfactory threshold under the same experimental conditions. Sensory analysis revealed that ethyl 3-hydroxybutanoate (S/R, 85:15, m/m) had an enhancing effect on the perception of fruity aromas in the matrices studied. Sensory profiles highlighted the contribution of ethyl 3-hydroxybutanoate to red-berry and fresh-fruit descriptors, despite its subthreshold concentrations.
authors.affiliation: Univ. Bordeaux, ISVV, EA 4577, Unité de recherche Œnologie, 33882 Villenave d'Ornon, France.|INRA, ISVV, USC 1366 Œnologie, 33882 Villenave d'Ornon, France.
authors.forename: Georgia
authors.initials: G
authors.lastname: Lytra
authors.affiliation: Univ. Bordeaux, ISVV, EA 4577, Unité de recherche Œnologie, 33882 Villenave d'Ornon, France.|INRA, ISVV, USC 1366 Œnologie, 33882 Villenave d'Ornon, France.
authors.forename: Margaux
authors.initials: M
authors.lastname: Cameleyre
authors.affiliation: Univ. Bordeaux, ISVV, EA 4577, Unité de recherche Œnologie, 33882 Villenave d'Ornon, France.|INRA, ISVV, USC 1366 Œnologie, 33882 Villenave d'Ornon, France.
authors.forename: Sophie
authors.initials: S
authors.lastname: Tempere
authors.affiliation: Univ. Bordeaux, ISVV, EA 4577, Unité de recherche Œnologie, 33882 Villenave d'Ornon, France.|INRA, ISVV, USC 1366 Œnologie, 33882 Villenave d'Ornon, France.
authors.forename: Jean-Christophe
authors.initials: JC
authors.lastname: Barbe
mesh_terms: D000328:Adult; D002087:Butyrates / Q000737:chemistry*; D002849:Chromatography, Gas; D005260:Female; D005421:Flavoring Agents / Q000737:chemistry*; D006801:Humans; D008297:Male; D009812:Odorants / Q000032:analysis; D012677:Sensation; D012903:Smell; D013237:Stereoisomerism; D014920:Wine / Q000032:analysis*; D055815:Young Adult
chemical_list: D002087:Butyrates; D005421:Flavoring Agents; C000609676:ethyl 3-hydroxybutanoate
keywords: chiral GC; enantiomers; enhancing effect; ethyl 3-hydroxybutanoate; fruity aroma; perceptive interactions; red wine