A natural alternative to sulphur dioxide for red wine production: Influence on colour, antioxidant activity and anthocyanin content

An alternate to sulphur dioxide natural antioxidant was tested during 2005 harvest on four different red vinifications, and was applied in each winemaking batch in combination with sulphur dioxide and on its own. Responses measured and analysed with uni- and multivariate statistics were: anthocyanin content, antioxidant capacity and classic oenological parameters. ANOVA revealed no significant effect of treatment in the antioxidant values of RA or diphenylpicrylhydrazyl (DPPH) of wines, but a paired t-test could differentiate wines treated only with SO₂ from those treated only with the novel product according to their RA values. Principal component analysis (PCA) of anthocyanin content of the treated wines gave five significant components, explaining 100% of variance and differentiating products treated only with SO₂ from those treated only with new product. PCA of oenological data explained 72% of variance in the first two components and wines were clearly differentiated on the basis of SO₂ or alternative treatment. In all cases, commercially acceptable red wines were produced, giving a possibility for partial substitution of SO₂ by a natural product.