Element concentrations in Chianti Classico appellation wines.

The concentrations of 21 elements (Al, B, Ba, Ca, Cd, Cr, Cu, Fe, K, Mg, Mn, Na, Ni, P, Pb, S, Si, Sr, Ti, V and Zn) were determined in wine samples of the very popular Italian Chianti Classico appellation, vintage 1997. Concentrations of most elements in Chianti Classico wines fell in the range of European red wines. Data variability (expressed as a coefficient of variation, CV) was maximum for elements more prone to exogenous contamination such as Cu (a residue of vineyard treatments; CV = 165), Pb (from atmospheric contamination; CV = 99) or Ni (from wine-making contamination; CV = 78). With respect to the results of a previous survey on 1987 vintage wines (n = 24) from the same appellation, levels of Mn, Cr, Pb and Cd decreased by a factor of 1.65, 1.84, 2.67, and 3.00, respectively. The improved quality and standard of hygiene in wine-making, and the phasing out of leaded gasoline during the last decade are probably responsible for these results. No differences were found for Al, Mg, Fe and Zn. The principal component analysis successfully distinguished Chianti Classico wines from Chianti and Venetian Cabernet Sauvignon, which were analysed for comparison. Seven elements (Al, Mg, Ca, K, Sr, Mn and Si) described a distinctive pattern. The classification success rate was lower for the two Tuscan wines because of similarities in the growing environment and variety composition. However, several elements appear as important chemometric parameters for developing a specific system to protect the designation of origin of Chianti Classico wines.