Multivariate differentiation of Spanish red wines according to region and variety

A total of 20 analytical parameters, including alcohols, total polyphenols and anthocyanins, colour and several normal oenological variables such as pH, total acidity and dry extract, were analysed in 66 red wines from two regions of Spain (Aragón and Navarra), made with seven different varieties of grapes (Graciano, Tempranillo, Grenache, Carignan, Merlot, Ruby Cabernet and Cabernet Sauvignon). Factor analysis of raw data provided a good description of the differences between production zones. With the exception of Ruby Cabernet, which presented very outstanding characteristics, grape variety characterisation was more difficult. In this sense, better results were obtained by means of stepwise discriminant analysis. At the end of the discriminant selection process, 94% of the training wines and 85% of the test wines were correctly classified by variety. These percentages were 89% (training sample set) and 92% (test wines) in the classification model obtained from the region.