title: Quantitative analysis, occurrence, and stability of (E)-1-(2,3,6-Trimethylphenyl)buta-1,3-diene in wine.
abstract: A stable isotope dilution assay has been developed for quantification of (E)-1-(2,3,6-trimethylphenyl)buta-1,3-diene (4) in wine using a [(2)H(6)]-analogue. Using this method, 4 was found in 96 out of 97 white wines, but in none of 12 red wines analyzed. 4 was found to be most prevalent in Semillon wines, followed by Chardonnay, with Riesling showing the least amount of 4 among these three varieties. 4, like 1,1,6-trimethyldihydronaphthalene (TDN, 3), appears to be formed during the aging process. 4 was found to be unstable in model wine, and in both white and red wine, with the order of stability being model > white > red. In a PVPP-stripped red wine, the rate of degradation of 4 was substantially lessened, with the final concentrations very close to those observed in model wine. When treated with either grape or wine tannin extracts in model wine, the concentration of 4 was found to decrease to levels very close to those observed with an untreated red wine. When white wine was heated at 45 degrees C, 4 was formed, indicating the presence of precursor forms. The amounts formed were much higher than those found in a commercial white wine. 4 was also observed in red wine heated to 45 degrees C, but the concentration produced was much less than that with white wine.
authors.affiliation: School of Chemistry, Physics and Earth Sciences, Flinders University, P.O. Box 2100, Adelaide, South Australia 5001, Australia.
authors.forename: Agnieszka
authors.initials: A
authors.lastname: Cox
authors.forename: Dimitra L
authors.initials: DL
authors.lastname: Capone
authors.forename: Gordon M
authors.initials: GM
authors.lastname: Elsey
authors.forename: Michael V
authors.initials: MV
authors.lastname: Perkins
authors.forename: Mark A
authors.initials: MA
authors.lastname: Sefton
mesh_terms: D000475:Alkenes / Q000032:analysis* / Q000737:chemistry; D002073:Butanes / Q000032:analysis* / Q000737:chemistry; D004355:Drug Stability; D005419:Flavonoids / Q000032:analysis; D008401:Gas Chromatography-Mass Spectrometry; D009682:Magnetic Resonance Spectroscopy; D010636:Phenols / Q000032:analysis; D059808:Polyphenols; D014920:Wine / Q000032:analysis*
chemical_list: C480593:1-(2,3,6-trimethylphenyl)buta-1,3-diene; D000475:Alkenes; D002073:Butanes; D005419:Flavonoids; D010636:Phenols; D059808:Polyphenols