title: Characterization of Atypical Off-Flavor Compounds in Natural Cork Stoppers by Multidimensional Gas Chromatographic Techniques.
abstract: Natural cork stoppers with sensory deviations other than the typical cork taint were subgrouped according to their sensory descriptions and compared with unaffected control cork stoppers. The assessment of purge and trap extracts obtained from corresponding cork soaks was performed by heart-cut multidimensional gas chromatography-olfactometry (MDGC-O). The identification of compounds responsible for atypical cork taint detected in MDGC-O was further supported with additional multidimensional GC analysis in combination with mass spectrometric detection. Geosmin and 2-methylisoborneol were mainly found in cork stoppers described as moldy and cellarlike; 3-isopropyl-2-methoxypyrazine and 3-isobutyl-2-methoxypyrazine were found in cork stoppers described with green attributes. Across all cork subgroups, the impact compound for typical cork taint, 2,4,6-trichloroanisole (TCA), was present and is therefore a good marker for cork taint in general. Another potent aroma compound, 3,5-dimethyl-2-methoxypyrazine (MDMP), was also detected in each subgroup, obviously playing an important role with regard to the atypical cork taint. Sensory deviations possibly affecting the wine could be generated by MDMP and its presence should thus be monitored in routine quality control.
authors.affiliation: Kompetenzzentrum Weinforschung, Dienstleistungszentrum Ländlicher Raum Rheinpfalz , Breitenweg 71, 67435 Neustadt an der Weinstraße, Germany.|Fakultät für Chemie, Universität Duisburg-Essen , Universitätsstraße 5, 45141 Essen, Germany.
authors.forename: Petra
authors.initials: P
authors.lastname: Slabizki
authors.affiliation: Rudolf Ohlinger GmbH & Co. KG , Industriestraße 5-7, 67136 Fußgönheim, Germany.
authors.forename: Claus
authors.initials: C
authors.lastname: Fischer
authors.affiliation: Kompetenzzentrum Weinforschung, Dienstleistungszentrum Ländlicher Raum Rheinpfalz , Breitenweg 71, 67435 Neustadt an der Weinstraße, Germany.|Fachrichtung Lebensmittelchemie und Toxikologie, Fachbereich Chemie, Technische Universität Kaiserslautern , Erwin-Schrödinger-Straße 52, 67663 Kaiserslautern, Germany.
authors.forename: Charlotte
authors.initials: C
authors.lastname: Legrum
authors.affiliation: Kompetenzzentrum Weinforschung, Dienstleistungszentrum Ländlicher Raum Rheinpfalz , Breitenweg 71, 67435 Neustadt an der Weinstraße, Germany.|Fakultät für Chemie, Universität Duisburg-Essen , Universitätsstraße 5, 45141 Essen, Germany.
authors.forename: Hans-Georg
authors.initials: HG
authors.lastname: Schmarr
mesh_terms: D002849:Chromatography, Gas / Q000295:instrumentation / Q000379:methods; D005421:Flavoring Agents / Q000032:analysis*; D018857:Food Packaging / Q000295:instrumentation*; D006801:Humans; D013058:Mass Spectrometry; D029963:Quercus / Q000737:chemistry*; D013649:Taste; D014920:Wine / Q000032:analysis*
chemical_list: D005421:Flavoring Agents
keywords: GC × GC-MS; alkylmethoxypyrazines; chloroanisoles; chloroveratroles; cork; heart-cut MDGC; musty off-flavor; olfactometry