title: Matrix-calibrated LC-MS/MS quantitation and sensory evaluation of oak Ellagitannins and their transformation products in red wines.
abstract: Aimed at investigating the concentrations and taste contribution of the oak-derived ellagitannins castalagin and vescalagin as well as their transformation products acutissimin A/B, epiacutissimin A/B, and beta-1-O-ethylvescalagin in red wine, a highly sensitive and accurate quantification method was developed on the basis of LC-MS/MS-MRM analysis with matrix calibration. Method validation showed good recovery rates ranging from 102.4 +/- 5.9% (vescalagin) to 113.7 +/- 15.2% (epiacutissimin A). In oak-matured wines, castalagin was found as the predominant ellagitannin, followed by beta-1-O-ethylvescalagin, whereas the flavano-C-ellagitannins (epi)acutissimin A/B were present in significantly lower amounts. In contrast to the high threshold concentration levels (600-1000 micromol/L) and the puckering astringent orosensation induced by flavan-3-ols, all of the ellagitannin derivatives were found to induce a smooth and velvety astringent oral sensation at rather low threshold concentrations ranging from 0.9 to 2.8 micromol/L. Dose/activity considerations demonstrated that, among all the ellagitannins investigated, castalagin exclusively exceeded its threshold concentration in various oak-matured wine samples.
authors.affiliation: Technische Universität München, Lise-Meitner Strasse 34, D-85354 Freising, Germany.
authors.forename: Timo
authors.initials: T
authors.lastname: Stark
authors.forename: Nadine
authors.initials: N
authors.lastname: Wollmann
authors.forename: Kerstin
authors.initials: K
authors.lastname: Wenker
authors.forename: Sofie
authors.initials: S
authors.lastname: Lösch
authors.forename: Arne
authors.initials: A
authors.lastname: Glabasnia
authors.forename: Thomas
authors.initials: T
authors.lastname: Hofmann
mesh_terms: D000328:Adult; D002853:Chromatography, Liquid / Q000379:methods*; D005260:Female; D005419:Flavonoids / Q000032:analysis; D006801:Humans; D047348:Hydrolyzable Tannins / Q000032:analysis* / Q000737:chemistry; D008297:Male; D009812:Odorants / Q000032:analysis; D029963:Quercus / Q000737:chemistry*; D015203:Reproducibility of Results; D012677:Sensation; D053719:Tandem Mass Spectrometry / Q000379:methods*; D013649:Taste; D014920:Wine / Q000032:analysis*
chemical_list: D005419:Flavonoids; D047348:Hydrolyzable Tannins