Wine Tannins: Where are they coming from? A method to access the importance of berry part on wine tannins content.

ABSTRACT Phenolic compounds are important constituents of red wine involved in its sensory properties. Although wine tannins can come from microbial and oak sources, the main sources of polyphenol remains grape skins and seeds. In order to better understand the grape seed and skin tannins contribution to the final wine tannins content, an original approach of winemaking has been set up. Our protocol explains a simple method to determine the percentage of skin and seed tannins extracted in wine all along the winemaking. The advantages of this method are presented below: • This method allows us to describe tannins extraction kinetics in wine according to the berry part (skins and seeds). • Additionally, our protocol allows to specifically determine the percentage of tannins extraction according to the winemaking stages (alcoholic fermentation and post-fermentative maceration) and the berry part (skins and seeds). • To sum up, this method serves to enhance the comprehension of tannins extraction process in wine according to the berry part.