Winemaker's Journal by George Troquato

Tannin

Anyone who has tasted young red wine should already be familiar with tannin – the clawing sensation that dries the mouth and grips the teeth. “The astringent feeling is probably the result of tannins binding with salivary proteins,” says Doug Adams of UC Davis. “Your tongue feels the roughness of the cheeks and gums because the lubricating proteins have been removed.”

Winemaker George Troquato

Along with alcohol and acid, tannin is one of the most essential components of wine, contributing to its structure, taste and ageability. It is extracted mainly from the skins, seeds and stems during red wine fermentation, or from oak barrels during the aging of whites or reds. Tannins are not much of a factor in white wines as their skins have less tannin and only their juice is fermented.

Tannins function as antioxidants to retard spoilage. According to Larousse’s Wines and Vineyards of France, “The richness in phenolic compounds, particularly tannins, is the main factor governing the longevity of wine.” Over time, oxygen ultimately triumphs as tannins give up the battle and fall as sediment.

While vital to the complexity and longevity of wine, tannins constitute a defect if their levels are too high or they are noticeably bitter. Estate and Vineyard Manager Ron Mosley and Winemaker George Troquato manage tannins at Cinnabar through the various stages of vine growth and fermentation.

Vineyard & Estate Manager Ron Mosley

In the vineyard
“The goal is to produce soft, ripe tannins along with ripe fruit,” says Ron. He encourages the production of uniform ripe fruit and tannins by:

exposing stems and skins to sunlight (colors darken)
sustaining adequate hang time (duration on vines)
developing a level of physiological maturity; not just sugar production

In the cellar
“There is a fine line between extracting sufficient tannins and over-extraction,” says George. He uses cellar practices that are dictated by the respective fruit:

gentle handling (conveyors instead of augers and less-intrusive pumps – in particular, one that gently pushes wine out of barrel with compressed nitrogen)
minimize jack-stem content during fermentation (they resemble game jacks)
avoid over-extraction of fruit and minimize maceration (contact) of seeds and stems
aging in properly seasoned barrels made by the best coopers

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