Abstract: Wine phenolic composition depends on the grapes used to make the wine and on the vinification conditions and a wide range of variables such as cultivar, viticulture practices and vinification techniques can affect the phenolic composition of red wines. Changes in polyphenol content and antioxidant activity during storage over 6 months in bottles were studied in Monastrell varietal red wines from grapes obtained by organic and conventional agricultural practices. Also it was studied the relationship between antioxidant activity and phenolic compounds. The results showed that the contents of anthocyanins decreased during storage although hydroxycinnamics derivatives, stilbenes and flavonols do not suffer significative changes. The total antioxidant activity of conventional and organic wines was well correlated especially with anthocyanins at first month of storage and flavonols all time. Stilbenes had a high correlation with antioxidant activity in both types of wine especially in the last month of storage ( r2 = 0.74), and hydroxycinnamic derivatives had a poor correlation with antioxidant activity. Evolution of phenolics compounds and antioxidant activity in conventional and organic wines were similar during storage. Not significant differences were observed in conventional and organic wines. © Springer Science & Business Media B.V.
Reference: Mulero, J., Pardo, F., & Zafrilla, P. (2009). Effect of principal polyphenolic components in relation to antioxidant activity in conventional and organic red wines during storage. European Food Research & Technology, 229(5), 807-812. Available online at: http://dx.doi.org/10.1007/s00217-009-1117-x