Tannins in wine, what are they ?
Essential technological tools in oenology.
Tannins are natural molecules from the polyphenol family that are found in many plant species.
The tannins used in oenology can be classified into three families which are distinguished by unique chemical strcutures, defining their oenological properties. The three tannic families are as follows :
The different properties of tannins in oenology.
Each oenological tannin allows a specific action according to its botanical origin and its molecular structure. The dosage used and the timing of use during the wine-making process can have an impact on :
What are winemaking tannins use ?
Ellagic Tannins
Botanical origin :
Ellagic tannins are part of the larger family of hydrolyzable tannins which also includes gallic tannins.
Ellagic tannins are exclusively extracted from oak and chesnut woods.
Oenological properties :
Ellagic tannins are characterized by a formidable efficiency on the following actions :
– Fining of wines
– Clarification of wines
– Refining / protection of the organoleptic character
Gallic Tannins
Botanical origin :
Belonging to the family of hydrolysable tannins, gallic tannins have several possible plant origins.
They are mainly derivated from oak gall nut and tara wood.
Oenological properties :
Gallic tannins have interesting properties :
– Contributes to the aromatic purity of wines
– Inhibition of oxidative enzymes
– Perfects mouthfeel
Condensed Tannins
Botanical origin :
Condensed tannins are also called proanthocyanidic or catechin tannins.
They are found in grape skins and seeds, quebracho wood, exotic woods (mimosa, green tea, cherry wood…).
Oenological properties :
Condensed tannins are particularly effective on three main criteria :
– Color stabilization
– Structure improvement
– Antioxidant protection