title: Geographic origin of southern Brazilian wines by carbon and oxygen isotope analyses.
abstract: We present a method that can differentiate between the varieties of grapes and the vintages of wines and show the relationship between the grapes, the wine and the geographic location. The place of origin and its geographic and climatic characteristics were determined by the isotopic ratios, (13)C/(12)C of the ethanol and (18)O/(16)O of the water content of wine (wine water), for southern Brazil wines. The producing subregions of Pinto Bandeira, Vale dos Vinhedos and Nova Pádua showed differences in the temperature, rainfall and humidity conditions used for the production under microvinification conditions of Merlot and Cabernet Sauvignon varieties, in the harvests of 2005 and 2006. An isotope ratio mass spectrometer coupled to an elemental analyzer was used to measure the (13)C/(12)C of ethanol and the (18)O/(16)O of wine water. Regardless of the grape variety used, it was possible to determine the subregion through measurement of the δ(18)O values in both harvests. The altitudes of the different subregions led to statistical differences and demonstrated an influence mainly on the δ(18)O values of wine water. The δ(18)O value of wine water was determined to be more selective for the determination of the cultivation subregions than the δ(13)C value of the ethanol. The altitude and latitude influenced mainly the δ (18)O values of wine water and the ethanol. The climatic influences are more noteworthy in distinguishing the year of the harvest than the cultivation subregion.
authors.affiliation: Reference Laboratory Enologic/Brazilian Institute of Wine (IBRAVIN), Avenida da Vindima, 1855, CEP: 95084-470, Caxias do Sul, Rio Grande do Sul, Brazil. lgadami@gmail.com
authors.forename: Laurien
authors.initials: L
authors.lastname: Adami
authors.forename: Sandra Valduga
authors.initials: SV
authors.lastname: Dutra
authors.forename: Angela Rossi
authors.initials: AR
authors.lastname: Marcon
authors.forename: Gilberto João
authors.initials: GJ
authors.lastname: Carnieli
authors.forename: Carlos André
authors.initials: CA
authors.lastname: Roani
authors.forename: Regina
authors.initials: R
authors.lastname: Vanderlinde
mesh_terms: D000531:Altitude; D000704:Analysis of Variance; D001938:Brazil; D002247:Carbon Isotopes / Q000032:analysis*; D002980:Climate; D000431:Ethanol / Q000737:chemistry; D005843:Geography; D013058:Mass Spectrometry / Q000379:methods*; D010103:Oxygen Isotopes / Q000032:analysis*; D027843:Vitis / Q000737:chemistry* / Q000145:classification; D014867:Water / Q000737:chemistry; D014920:Wine / Q000032:analysis*
chemical_list: D002247:Carbon Isotopes; D010103:Oxygen Isotopes; D014867:Water; D000431:Ethanol