Updating Wine Pigments

I have proposed that the stabilized chromophores are essentially quinonoid, and that they are based upon the anhydro base structures substituted with flavan units. ..with further colour contribution from quinones moieties produced by slow oxidative changes 

Somers also concluded that these new pigments were much less sensitive than anthocya-nins to changes in the pH value of the medium, and quite resistant to discoloration by bisulfite. 

It is a fact that phenolic compounds, namely flavonoids, play a crucial role in wines as they are responsible for the color of red and white wines and contribute to their mouth characteristics (astringency and bitterness). In Vitis vinifera grapes and wines, this group of compounds is structurally diversified and comprises different classes of compounds, such as anthocyanins, flavan-3-ols (catechins and condensed tannins), flavonols, flavones, and dihydroflavonols. 

Two recent papers by Monagas et al. (2005) and Fulcrand et al. (2006) have made significant observations regarding the main structures of wine pigments and the mechanisms involved in their formation. 

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