UV-vis spectroscopy application to classify Spanish wine vinegars from different protected designation of origin and different aging categories

RIOS-REINA R.; AZCARATE S.M.; CALLEJÓN R.

Cordoba

Congreso; VII Congreso Internacional de Ciencia y Tecnología de Alimentos (CICYTAC 2018); 2018

Nowadays, there is a growing consumer?s demand for food products with a high quality. Protected Designation of Origin (PDO) is one of the label adopted by the European Community as recognition of some specific food quality attributes. Among the PDO products, some wine vinegars, that are traditionally linked to a specific geographical area and made by a traditional method, are found. Within these high-quality wine vinegars, three important Spanish wine vinegars have been protected by three different PDOs because of their unique characteristics and traditional production: ?Vinagre de Jerez? (also known as ?Sherry wine vinegar?), ?Vinagre de Condado de Huelva? and the most recently ?Vinagre de Montilla-Moriles?. These vinegars have high prices in the market due to their high quality, the long aging time and the high cost of production. That explains that adulteration and unfair competition in the vinegar industry are commonly practiced, leading to the need of characterizing and differentiated them. In this context, different analytical techniques have been applied for extensive characterization and authentication. However, UV-vis spectroscopy has not been studied yet for classification of wine vinegars, although it has been applied in many other food authenticity studies. For this reason, the potential of UV-vis spectroscopy has been investigated as a rapid, inexpensive and non-destructive methodology for vinegar characterization and classification considering Spanish PDO wine vinegars and their registered aged categories. Spectra from 40 wine vinegars of different categories within the 3 PDOs and 11 wine vinegars without a PDO (so-called rapid vinegars) have been analyzed and compared in the region of 280-740 nm. Principal component analysis (PCA) was performed to detect groupings, outliers and structures in the data. Soft independent modelling of class analogies (SIMCA) was used to build classification models for category classification within each PDO and also for PDO classification. PCA showed a clearly difference between PDO vinegars of the same category, and also a trend of grouping from the less aged to the most aged vinegars within each PDO. A clarly differentiation between PDO and non-PDO wine vinegars was also observed. The results demonstrated that the use of the analytical and chemometric methodology proposed is a perfect combination to differentiate and authenticate wine vinegars belonging to different categories and origins. The advantages of this technology (e.g. fast and no-destructive methodology) would allow implementing this measurement as an additional control for PDO councils and producers to assess the authenticity of PDO, categories, and to monitor the aging process.