Comparative analysis of red wines on the base of optical and chemical characteristics by statistical methods

Thirty – five samples of red wines from different geographic regions have been characterised according to 14 basic optical and chemical characteristics - colour parameters, content of anthocyanins and antioxidant activity. The goals of this study is to compare the tested wines using different statistical methods. Conducting hierarchical cluster analysis the samples have been divided into 4 clusters according to their difference and similarity. The result is presented graphically by a dendrogram. It could be concluded that the optical parameters and related chemical indicators are more decisive for the division of wines based on the region of production than on the basis of the predominant grape variety. The total number of studied parameters was reduced to 4 factors by factor analysis using Principle Component Analysis (PCA). These new factors explained 86.75% of the entire variation. The first factor contained chemical parameters and color coefficients in SIELab colorimetric system. The second one was connected with the quality characteristics of wine, which were important for consumers such as brilliance of red, color intensity. The third and the fourth factors were related with the Hues angles, color parameter b and saturation for the red wines.