Differentiation between Croatian dessert wine Prošek and dry wines based on phenolic composition

The phenolic composition of the Croatian dessert wine Prošek and dry wines Plavac mali and Pošip produced from the same autochthonous cultivars was investigated to determine which phenolic compounds best discriminate between these wine types. The wines were analyzed by the targeted metabolomic method using UPLC/QqQ-MS/MS. Forty-five (45) phenolic compounds were identified and classified into five groups based on chemical structure: benzoic acid derivatives, cinnamic acid derivatives, flavan-3-ols, stilbenes and flavonols. ANOVA indicated that the grape-drying process heavily influences the complex phenolic composition of Prošek dessert wine, which differs significantly from dry wines produced from the same cultivars. The data was grouped by principal component analysis and linear discriminant analysis to derive a classification function that distinguished dry and dessert wines with 98% accuracy. Principal component analysis separated the samples and showed that 23 phenolic compounds depending to phenolic acids, phenolic aldehydes, flavan-3-ols and flavonols were the compounds that best differentiated the Prošek from the dry wines.