Relatively more common and dangerous wine faults (also acetic acid engraving, volatile acid ), which is due to excessive quantities acetic acid is caused in the wine. Starting point of the process are Acetobacter (Acetic acid bacteria), which can already form on injured or cracked grapes in the vineyard and in the grape reach. In the transmission and dissemination also plays the Essigfliege a role. These bacteria form over the intermediate acetaldehyde out alcohol the acetic acid. Likewise, too Lactic acid bacteria be the cause. Incompletely filled wine containers with one whitespace favor the process of acetic acid formation by the influence of oxygen. The most common is the vinegar in the maceration from red wines because the relatively high amount of oxygen in the mash enhances the process.
The wine is higher colored (Brownish), occasionally forms on the surface also a slimy, slightly cloudy pellicle, It smells vinegar-like unpleasant sour and pungent, the taste is angry - sharp, Such a wine is called at a tasting volatile (volatile). The best provision is the most embarrassing hygiene, Avoidance of oxygen access as well sulphurize the mash. In wine, the error can only be fought more difficult, which by reversal osmosis and then ion exchange is tried. If due to large quantities Acetic acid ethyl ester by reaction of acetic acid with alcohol and thereby metabolic products of wine defects Uhuton occurs, the vinegar is sensory strengthened. See also below vinegar,