Rapid discrimination of Italian Prosecco wines by head-space gas-chromatography basing on the volatile profile as a chemometric fingerprint

Prosecco wine is one of the most important products of the Italian oenological landscape. Its production is strictly regulated by several disciplinary. Thus, it is important to verify the quality of the final product, to defend the uniqueness of this wine. This work describes a rapid method to discriminate among varieties of Italian Prosecco wine using the volatile-fraction distribution as an untargeted fingerprint. The volatile profile corresponds to gas-chromatograms obtained in head-space mode. Principal components analysis of chromatograms allows discriminating the Prosecco samples depending on geographical origin, cultivation practices, and wine-making technologies. In particular, conventional vs. biological agriculture and manual vs. mechanical harvesting give well-separated clusters when projected on a scores plot. Influence plots allow evaluating which variables are the most effective to describe the differences between oenological classes, which are declared in the label and coded in the disciplinary of origin denomination. The identification of discriminating molecules in the volatile profile is also performed by Kovats indexes. Thus, possible chemical markers for the classification of Italian Prosecco wines are appointed.