Classification of red wines from controlled designation of origin by ultraviolet-visible and near-infrared spectral analysis

Abstract

Spectroscopy has become one of the most attractive and commonly used methods of analysis in many agricultural products. Chemometrics combined with ultraviolet (UV), visible (VIS) and near-infrared (NIR) spectral analysis were evaluated to classify wines between two controlled designation of origin (DO) of Spain (Rías Baixas and Riberia Sacra). The aim of this work was to determine the feasibility of using the UV-VISNIR spectroscopy combined with chemometrics tools to discriminate between red wines of different DO. Support Vector Machine (SVM) and Linear Discriminant Analysis (LDA) were applied to classify the red wines by their UV-VIS-NIR spectra. Several pre-treatments were applied to improve the classification. The best classification of red wines was obtained in UV-VIS-NIR raw data for LDA models (100% of classification). Results of classification with SVM classification models were slightly lower than LDA results (97.3% for the pretreatment Centred and scaled). This shows the importance of a good selection of the chemometric method of classification. UV, VIS and NIR spectral data with chemometrics tools showed the feasibility of classifying red wines.