Characterization of the phenolic profile of commercial Montenegrin red and white wines

The phenolic characterization was conducted on 43 commercial red (Vranac, Kratošija, and Cabernet Sauvignon) and white (Krstač and Chardonnay) Montenegrin wines during the vintages of 2015 and 2016. Several phenolic groups were determined: total anthocyanins, low- and high-molecular-weight proanthocyanidins. Non-flavonoids, such as phenolic acids (seven hydroxycinnamic acid derivatives—tartaric esters and free forms, and hydroxybenzoic acid derivatives—gallic acid), and stilbenes (resveratrols trans/cis isomers and their 3-glucosides) were analyzed by HPLC–UV and HPLC–DAD, respectively. Red wines reported higher concentrations of phenolic compounds and antioxidant properties, these parameters being strongly correlated. Among red wines, Cabernet Sauvignon in 2015 reported the highest content of total phenols (2197 mg L⁻¹), low and high content of proanthocyanidins and antioxidant activity (20.0 mM L⁻¹), respectively, and the lowest content of stilbenes (1.15 mg L⁻¹). Vranac wines showed the highest content of anthocyanins (799–810 mg L⁻¹). Kratošija wines reported the highest content of hydroxycinnamic acids (92.0–97.7 mg L⁻¹) in both vintages. Among white wines, in the 2016 vintage, Krstač reported higher contents of total phenols and stilbenes (300 and 0.41 mg L⁻¹, respectively) when compared with Chardonnay wines (226 and 0.12 mg L⁻¹, respectively). The results showed that the variety influences the content and composition of hydroxycinnamic acid derivatives and stilbenes. The same was verified in vintages, where edaphoclimatic conditions probably influenced the results obtained. The wines studied were differentiated and discriminated. The factor variety was always present and sometimes it was difficult to classify wines according to the vintage, showing that the varietal factor prevails.