γ decalactone

Dichloromethane and anhydrous sodium sulfate were purchased from VWR (Darmstadt, Germany) whereas sulfuric acid and sodium carbonate were from Roth (Karlsruhe, Germany). The reference substances were obtained from the following suppliers: acetic acid, 2-phenylethanol, 3-methyl-1-butanol (isoamyl alcohol), hexanoic acid, phenylacetic acid, ethyl 2-methylbutanoate, γ-decalactone, γ-undecalactone, 2-methylbutanoic acid and 3-(methylthio)-propanal (methional) were from Sigma-Aldrich (Steinheim, Germany), butanoic acid and ethyl butanoate from Fluka (Steinheim, Germany), 2-methylpropanoic acid (isobutanoic acid) from SAFC (Steinheim, Germany), and 4-hydroxy-3-methoxybenzaldehyde (vanillin) from ABCR (Karlsruhe, Germany). The isotopically labeled standards were purchased from the following suppliers given in parentheses: 3,4-²H₂-3-methyl-1-butanol (²H₂₋isoamyl alcohol), 1,3,4,5,6-²H₅-2-phenylethanol, 3-(methyl-²H₃-thio)-propanal (²H₃-methional), 5,5,6,6-²H₄-y-decalactone, 6,7-²H₂-y-undecalactone (Aromalab, Freising, Germany), 6,6,6-²H₃-hexanoic acid, 3,3,3-²H₃-2-methylpropanoic acid (²H₃-isobutanoic acid), and ²H₆-ethanol (CDN Isotopes, Pointe-Claire, Quebec, Canada), 1,2-¹³C₂-butanoic acid, α,β-¹³C₂–phenylacetic acid, ¹³C₁-acetic acid, and 4-hydroxy-3-methoxy-¹³C₆₋benzaldehyde (¹³C₆-vanillin) (Sigma-Aldrich, Steinheim, Germany).

Reference compounds of the odorants identified
were obtained from the commercial sources given in parentheses: acetic
acid (Merck, Darmstadt, Germany); butane-2,3-dione, butanoic acid,
γ-decalactone, δ-decalactone, γ-dodecalactone, δ-dodecalactone,
ethyl butanoate, ethyl hexanoate, 5-ethyl-3-hydroxy-4-methyl-2(5H)-furanone, hexanoic acid, 3-hydroxy-4,5-dimethyl-2(5H)-furanone, 4-hydroxy-3-methoxybenzaldehyde (vanillin),
2-isopropyl-3-methoxypyrazine, 3-methylbutanal, 2-methylbutanoic acid,
3-methylbutanoic acid, 3-methylbutanol, 2-methylpropanoic acid, γ-nonalactone,
(E)-2-nonenal, pentanoic acid, 2-phenylacetic acid
and 2-phenylethanol (Sigma-Aldrich Chemie, Taufkirchen, Germany);
and 4-ethyloctanoic acid (ABCR GmbH & Co. KG, Karlsruhe, Germany).
The following reference compounds were synthesized as previously
described: (Z)-2-nonenal^{27 (link)} and trans-4,5-epoxy-(E)-2-decenal.^{28 (link)}

Sodium chloride and hexane (≥95%) were obtained from Fisher Scientific (Pittsburgh, PA, USA). Sodium sulphate (anhydrous) was obtained from ECP-Analytical (Auckland, New Zealand). 4-Decanone* (≥97.0%) was obtained from Tokyo Chemical Company (Tokyo, Japan). 4-Methyl-2-pentanone* (≥98%) was obtained from BDH Chemicals Ltd. (Poole, UK). Dichloromethane (≥99.9%), methanol (≥99.8%), sodium hydroxide solution (1N), 3-octanone (≥98%), δ-octalactone (98%), γ-decalactone (≥98%), δ-decalactone (≥98%), γ-dodecalactone (≥97%), δ-dodecalactone (≥97%), δ-tetradecalactone (98%) were obtained from Merck (Darmstadt, Germany). A C₇-C₃₀ Saturated Alkane Standard was obtained from Supelco (Bellefonte, PA, USA). Liquid nitrogen, liquid carbon dioxide, hydrogen carrier gas (instrument grade, >99.98%), and nitrogen (instrument grade, >99.99%) were obtained from BOC Ltd. (Auckland, New Zealand).