Antioxidant activity, phenolic content and colour of the Slovak cabernet sauvignon wines

Antioxidants are specific substances that oxidize themselves and in this way they protect other sensitive bioactive food components against destruction. At the same time, they restrict the activity of free radicals and change them to less active forms. Grapes and wine are a significant source of antioxidants in human nutrition. One of the most important group occuring in grapes and wines are polyphenols. Many of phenolic compounds have been reported to have multiple biological activities, including cardioprotective, anti-inflammatory, anti-carcinogenic, antiviral and antibacterial properties attributed mainly to their antioxidant and antiradical activity. Therefore, it is important to know the content of polyphenols and their antioxidant effects in foods and beverages. Twenty-eight Cabernet Sauvignon wine samples, originated from different Slovak vineyard regions, were analyzed using spectrophotometry for the content of total polyphenols, content of total anthocyanins, antioxidant activity and wine colour density. Determined values of antioxidant activity in observed wines were within the interval 69.0 - 84.2% inhibition of DPPH (average value was 78.8% inhibition of DPPH) and total polyphenol content ranged from 1,218 to 3,444 mg gallic acid per liter (average content was 2,424 mg gallic acid.L-1). Determined total anthocyanin contents were from 68.6 to 430.7 mg.L-1 (average content was 220.6 mg.L-1) and values of wine colour density ranged from 0.756 to 2.782 (average value was 1.399). The statistical evaluation of the obtained results did not confirm any linear correlations between total polyphenol content, resp. total anthocyanin content and antioxidant activity. The correlations between total polyphenol content and total anthocyanin content, resp. the content of total anthocyanins and wine colour density were strong. The results confirmed very strong correlations between wine colour density and total polyphenol content, resp. antioxidant activity