The tartaric stabilization of wine

Sometimes when you open a bottle of wine you can see the presence of crystals in the bottom of the bottle. What exactly are these crystals and what are the consequences of their presence in the wine?

As you know, the wine is a mixture of water, alcohol and various components. Among these are organic acids. The main acids found in wine are the malic acid and lactic acid (which we discussed earlier) and tartaric acid. Today we’ll look at the latter which is responsible for the formation of crystals in question.


The tartaric acid is an acid-specific vineyard. It is found only in this plant and its fruit. This acid is involved greatly sensations in the mouth during tasting. It balances the sensations of heat, fat and roundness caused by the presence of alcohol. It is this specificity that I think has helped the growth of wine as a beverage.

But this famous tartaric acid has a peculiarity quite embarrassing for the winemaker.
Simply put, it is usually soluble in wine, however, under certain conditions it may crystallize and thus form a deposit. If the wine meets these conditions once bottled, you can observe small translucent crystals at the bottom of your bottle.

Of course this deposit does not affect the qualities of the wine. The only problem is aesthetic: many consumers reject a wine with this kind of specificity. The wine does not appear natural and some even think that the crystals are powdered sugar.
Note that the cooling of the wine will cause crystallization of tartaric acid. Thus it is possible to cause the formation of crystals just by a bottle of wine cool or keeping it in your cellar.

To avoid the formation of these crystals the winemaker will cause precipitation of tartaric acid before bottling. This is called tartaric stabilization. The wine is cooled to temperatures close to zero to cause the formation of crystals, then the wine is filtered.
This technique requires a lot of energy to keep wine cold for several days. Note past this stabilization was done naturally with the influence of cold winter (but the risk remains significant rainfall in bottles with this technique).
Other processes can also remove the excess tartaric acid or prevent crystal formation.

Note that this issue is especially problematic precipitation for white wines or roses as the color intensity of red wines can hide the presence of crystals. And above all remember you that these crystals do not pose problems visually.