Analysis of some metals in wine by means of capillary electrophoresis.: Application to the differentiation of Ribeira Sacra Spanish red wines

The content of some metals (Na, K, Ca, Mg, Mn and Li) in a variety of red wines produced in different geographical zones of Galicia was determined in a single analysis by capillary electrophoresis. Data were processed using multivariate supervised and non-supervised chemometric techniques involving cluster analysis, principal component analysis (PCA), linear discriminant analysis (LDA), K nearest neighbours (KNN) and soft independent modelling of class analogy (SIMCA). The results obtained have allowed for the categorisation of wine samples according to their origin; the wines with Ribeira Sacra Certified Brand of Origin (CBO) can be differentiated from the wines of two other CBO from Galicia: Ribeiro and Valdeorras. The latter two types of wine are made with the same or similar grape varieties; hence, due to their similar organoleptic properties they are possible substitutes for the falsification of Ribeira Sacra wines.