Quality characteristics, polyphenol profile and antioxidant capacity in red, rosé and white monovarietal wines from Ionian Islands of Greece [pdf]

Background. Wine is one of the oldest traditional alcoholic beverages consumed worldwide. In addition, red and white wines are an excellent source of antioxidant compounds. Numerous studies have focused on the analysis of phenolic acids and flavonoids of several wines originating from organic and conventional culti-vars growing grapes. However, to the authors best knowledge, there are no research papers dealing with the phenolic content of wines made on the Ionian Islands so far. Materials and methods. The amount of total phenolics, total flavonoids, total anthocyanins, total tannins, the concentrations of individual phenolic compounds, as well as the antioxidant capacity, were used syner-gistically to assess the compositional profile of eleven monovarietal wines. Results. As expected, red wines exhibited the strongest antioxidant profile. Vertzami was the richest variety in total phenols and antioxidant capacity, followed by the Avgoustiatis variety and Mavrodaphne variety. Regarding white wines, Thiako white had the highest total phenolic values, while Robola rose contained a similar total phenolic content as the white varieties. A highly positive correlation between the antioxidant capacity and polyphenol composition expressed as total phenolic, total flavonoid, total anthocyanin and total tannin content, was observed. Last, gallic acid and tyrosol were two of the major phenolic compounds de-tected in all tested wines. Conclusion. Our findings revealed that the amounts of phenolic contents and antioxidant activity vary sig-nificantly in different types of wines. The observed differences could be related to a range of variables such as geographical origin, aging, climate and the vinification techniques.