Classification of White Varietal Wines Using Chemical Analysis and Sensorial Evaluations

Katja Šnuderl,¹ Jan Mocak,^2,* Darinka Brodnjak-Vončina³ and Bibiana Sedláčková⁴

¹ Metrology Institute of the Republic of Slovenia, Tkalska 15, SI-3000 Celje, Slovenia
² University of Ss. Cyril and Methodius, Faculty of Natural Sciences, Nam. J. Herdu 2, SK-91701, Trnava, Slovakia
³ Faculty of Chemistry and Chemical Engineering, Smetanova 17, SI-2000 Maribor, Slovenia
⁴ Strečnianska 16, 85105 Bratislava, Slovakia
* Corresponding author: E-mail: jan.mocak@ucm.sk

Abstract
The ways of application of multivariate data analysis and ANOVA to classification of white varietal wines are here demonstrated. Wine classification was performed using the following classification criteria: wine variety, year of production, wine producer, and wine quality, as found by sensorial testing (bouquet, colour, and taste). Subjective wine evaluation, made by wine experts, is combined with commonly used chemical and physico-chemical properties, measured in analytical laboratory. Importance of the measured variables was determined by principal component analysis and confirmed by analysis of variance. Linear discriminant analysis enabled not only a very successful wine classification but also prediction of the wine category for unknown samples. The wine categories were set up either by three wine varieties, or two vintages, wine producers; two or three wine categories established by wine quality reflected either total points obtained in sensorial evaluation or the points obtained for a particular quality descriptor like colour, taste and bouquet.

Keywords: Multivariate data analysis; Principal component analysis; Discriminant analysis; Feature selection; ANOVA;
Sensory analysis