Possible Interaction: Anthocyanins and Tannins

“The addition of commercial tannins greatly promoted the level of gallic acid in the wine and led to a relatively higher concentration of anthocyanins.”

“Furthermore, anthocyanins significantly decreased the size of the condensed tannin extracted.”

“These results suggest that anthocyanins are not only enhancing the extractability of condensed tannin but also readily incorporating into the polymeric material, leading to a decrease in the average molecular mass of the condensed tannin polymer.”

“Concurrent modification of anthocyanin and tannin occur forming pigmented tannin, softening astringency and retaining persistent color.”

“The results indicated that anthocyanins favored skin and seed tannin extraction and that there is a competition for the adsorption sites between anthocyanins and tannins that increases the tannin content when anthocyanins are present.”

“This suggests that anthocyanins play an important role in tannin extractability, perhaps because they affect the extent of the tannin-cell wall interaction, a factor that largely controls the resulting quantity of tannins in wines.”

“Nevertheless, by means of cluster analysis and principal component analysis, it was observed that higher alcohols were significantly promoted by grape seed tannin while most anthocyanins can be improved by addition of grape tannins.”