3.3. Principal component analysis
To obtain an overall view of the influence of the dehydration process on the chemical composition and sensory characteristics of Cabernet Sauvignon and Merlot wines, principal component analysis (PCA) was performed (Fig. 2) with only the variables studiedthat contributed significantly to the separation of samples (>0.70)by previously factor analysis (data not shown). The PCA was performed using the two principal components (factor 1 factor 2)which explained about 86% of the variability. It should be noted that the wines were separated into three groups according to the per-
centage of dehydration applied to the grapes by Factor 1, which explains 77.41% the variability of the data. Note that the control wine samples were correlated with the content of total and individual monomeric anthocyanins and with the sensory appearance attribute of ruby red colour. The CSV40 and MV40 wines were mainly correlated with alcoholic content, polymeric anthocyanins,colour tonality, and with the sensory attribute of red orange colour,alcoholic sensation, bitterness and sweetness. On the other hand,the CSV30 andMV30 wines were related to the results obtained for
magnesium, sodium, calcium and protocatechuic acid. The principal component analysis showed that the different degrees of grape dehydration under controlled conditions influenced the chemical and sensory composition of the wines produced, yielding differentiated products.