Acid

Acidity is an important component of wine, preserves and gives a wine expression and character (sometimes also referred to as backbone).

Too little acidity results in a boring wine, too much acidity makes the wine undrinkable. Acidity in wine also emphasises the colour. So if a wine has a 'sparkling' or 'brilliant' appearance, this is not necessarily only due to the visually perceived purity of the liquid, but is also often associated with higher acidity. In general, warm wine-growing regions (e.g. Spain) require more sugar and less acidity in the vines, while cooler regions (e.g. Champagne) require less sugar and more acidity.

The acidity of champagnes is around 5 to 9.5g/litre. Wine contains several types of acid. More or less important acids such as tartaric acid (a strong fruit acid), malic acid (also a strong fruit acid), lactic acid (a mild acid) and tannins are represented, and it is also important to note carbonic acid in champagnes.

Tartaric acid is considered a rarity in fruits and is mainly associated with vines. It is considered somewhat stronger than malic acid. It is also described as more 'stable' than malic acid. It remains relatively constant as the grapes ripen, but in wine it degrades somewhat as potassium and calcium like to chemically combine with tartaric acid. It is also referred to as 'stable' because it is rarely attacked by bacteria. Cellar masters therefore tend to strengthen the acidity of their wines with tartaric acid rather than with the more 'unstable' malic acid, for example.

Malic acid, on the other hand, can be found in many fruits. In excess (like tartaric acid) it can have a strong flavour (in the sense of 'biting') in a wine. Malic acid is also often emphasised by unripe grapes. In contrast to tartaric acid, it increasingly degrades as the grapes ripen. In southern wine-growing regions, it is therefore often only slightly present when the grapes are harvested. During alcoholic fermentation, malic acid additionally degrades by approx. 15%. Under certain circumstances, it is also very aggressively attacked by certain bacteria during vinification. It is therefore considered to be rather 'unstable'. At the same time, however, malic acid is very important, be it in its skilful preservation in the wine or in its (natural or cellar master-assisted) degradation to lactic acid. As reading for Champagne Since only optimal grapes are allowed (Auslese), they are lower in yield for the winegrowers (and therefore more expensive), but offer Champagne predictable advantages over many other wines, which in some winegrowing regions of the world are often characterised by ruthless harvesting (quantity over quality). In the rather cool wine-growing region of Champagne, favourable acidity levels in the grapes are also often to be expected during the harvest.

Lactic acid in wine, on the other hand, does not come from the vines. It is produced in the wine in very small quantities during the fermentation of sugar to alcohol by the yeasts. After the alcoholic fermentation (over approx. seven to ten days), the so-called malolactic fermentation often takes place (approx. one month or even longer). During this fermentation, bacteria convert the natural malic acid into the gentler lactic acid. The wine also acquires complex flavours during this phase.

It is worth briefly mentioning the rather small amount of citric acid present in vines. It only accounts for approx. 5% of the acidity, but sometimes more in the case of noble rot on vines or botrytis. In addition, the carbonic acid must also be noted for champagnes.

 

 

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