Determinação da razão isotópica 87Sr/86Sr por ICP-MS no sistema solo-vinho

Mestrado em Engenharia Alimentar - Instituto Superior de AgronomiaOne of the most challenging matters regarding wine authenticity is the control of geographical provenance. The strontium isotope ratio 87Sr/86Sr has been suggested to be a promising fingerprint for wine provenance identification. It is based on the assumption that there is a correlation between the ratio 87Sr/86Sr of the wine and that of the soil in which the vine as grown. The aim of this study was to assess the 87Sr/86Sr ratios of vineyard soils from Portuguese DO and evaluate its suitability as a tool for provenance authentication It was optimized an analytical protocol for the determination of the isotopic ratio 87Sr/86Sr in soil-wine system by Q-ICP-MS .Due to isobaric overlap of 87Sr and 87Rb, Sr and Rb have to be separated prior Q-ICP-MS analysis. For an efficient removal of Rb a ion-exchangechromatography procedure using chelating properties of EDTA was optimized. ICP-MS instrumental parameters were optimized in order to obtain the best precision for the 86Sr/87Sr (0.1- 0.2% RSD). The 86Sr/87Sr ratios of soils from vineyards located in three Portuguese DO (Dão, Óbidos and Palmela), were determined. Significant differences were found between soils of different DO regions. The soil from Dão DO, developed on granites, showed statistically higher 87Sr/86Sr than other soils tested, developed on sedimentary formation