Name for hydrogen-containing, liquid or solid chemical compounds. The hydrogen ions cause the sourtaste a solution. One distinguishes between inorganic and Organic acids, In the wine are mostly organic acids of the group carboxylic acids in free, bound, and to a lesser extent in volatile form. The term "acid" is not meant to be negative, because without this important ingredient, a wine tastes good flat and slow. Only then does he get refreshing power, and that is how it comes about Sweet to better advantage. Wines from hot areas often have a lower content. Not mature grapes own different depending vine a high proportion.
Certain acids such as malic acid and tartaric acid are already present in the grapes, others such as acetic acid and lactic acid are only in the fermentation educated. For preservation, must or wine is also added to acids. For example ascorbic acid and sulfur dioxide, which is related to the water in the wine sulphurous acid forms. The acidity in wine refers to the amount or concentration of acids. This one is going through titration determined and expressed in g / l.
The acidity, on the other hand, expresses something completely different. The sour The taste of a liquid depends not only on the amount of acid alone, but also on its degree of dissociation. The degree of dissociation of an acid or base depends on its acid constant (or base constant), its concentration or the present PH value a solution. The most acidic is tartaric acid, which is almost three times as acidic as lactic acid and one and a half times as acidic as malic acid. Even less acidity have succinic acid and acetic acid.
The acids are in non-volatile acids and volatile acids the limit can not be drawn absolutely exactly (there are also medium-volatile acids, to be precise). The amount of all acids gives the total acidity, The three most common nonvolatile acids in wine are tartaric acid (0.5 to 4 g / l), malic acid (0.5 to 6 g / l) and citric acid (0.1 to 0.3 g / l), which make up about two thirds of the amount of all acids. The lactic acid (0.8 to 3.3 g / l) arises largely at the malolactic fermentation by conversion of the malic acid.
In smaller quantities there are still Succinic acid. galacturonic. gluconic. glucuronic. glycolic acid. oxalic acid. mucic and cinnamic acid, The non-volatile acids are shown in total as tartaric acid (although several are) in g / l. The most common volatile acidity is the acetic acid (0.15 to 0.5 g / l in healthy wine). As the name suggests, these are not contained in the wine, but evaporate slowly. They are referred to in sum as acetic acid (although several) and in g / l.
The amount of total acidity is at White wines about 4 to 9 g / l and at red wines about 4 to 6 g / l. Higher quantities carry by defense of microorganisms positive to durability at. Although EU legislation provides for an acid correction for musts and wines in principle, this depends on the growing zone is. In Zone A ( Germany except Baden) and B (growing area to bathe. Austria ) is a partial deacidification allowed, but one leavening prohibited in principle. The sulphurous acid is differentiated into free and bound. The two give the whole sulphurous acid whose share in wine is strictly limited. The acids are used in the aging or. bottle aging not dismantled. For other wine ingredients, see total extract,
All aids, works and measures in the vineyard during the growth cycle one finds below Weingarten Care, Complete listings of the numerous cellar techniques, as well as a list of the wine-regulated wine, sparkling wine and distillate types are under the keyword winemaking contain. Comprehensive information on wine law is available under the keyword wine law,