Determination of metallic elements in Chilean wines by atomic absorption spectroscopy and inductively coupled plasma–mass spectrometry
Abstract
The chemical composition of wines depends on series of variables such as the type of grape, edaphoclimatic conditions, and viticulture and winemaking practices employed during production. Metallic elements play a significant role during winemaking (e.g. as catalysts of oxidation reactions) and have been previously employed for the classification of wines according to provenance. In this work, we focused on the analysis of metallic elements (K, Na, Ca, Zn, Cu, Fe, Mg, Mn, Ni, Cr, Al, Pb, Cd, Hg, Se, Co, Sn and As) in 145 Chilean wine samples (102 reds and 43 white wines), of seven grape varieties, and five of the major wine producing regions in Chile. Metals determinations were performed by pretreatment with microwave acid digestion, and analysis with flame atomic absorption spectroscopy (AAS) and inductively coupled plasma–mass spectrometry (ICP-MS). The results obtained showed that the concentrations of major metal ions of Chilean wine were within the expected ranges observed in other wine regions. For instance, the average concentration of some of the elements assayed were: Fe, 2.012±1.40 mg/L; Zn, 0.71±0.53 mg/L; K, 799.15±252.74 mg/L; Na, 15.38±8.85 mg/L, and As, 0.04±0.02 mg/L. Moreover, statistical methods were applied for the interpretation of the data obtained, observing that there were significant differences in the content of elements such as As, Na, K, Mn, Cr (p < 0.05) among different grape-growing areas. The prior was used to discriminate among groups of samples according to geographical origin using multivariate statistics. Acknowledgements: FONDECYT grants Nº 3140293 and 1150725. Support from the Chilean Institute of Public Health (ISP) and UTalca’s Soils and Crops Technology Center (CTSYC) is also appreciated.
Issue: Macrowine 2016
Type: Poster
Authors
*Universidad de Talca