Reserve wine system, most DACs have an additional "Reserve" designation for a wine which has slightly more strict requirements. Before the 1971 German wine law, a term corresponding to reserve wine existed in "kabinett", sometimes written as "Kabinettwein". In 1971, the similar-sounding term "Kabinett" was instead introduced as the lowest level of the "Prädikatswein" category, i.e., with a completely different meaning. Therefore, in the present German wine classification no legally defined term corresponding to reserve wine exists. Reserve wine Reserve wine is wine of a higher quality than usual, or a wine that has been aged before being sold, or both. Traditionally,
Wine fault spoilage yeasts and bacteria. This can be from either a by-product of fermentation, or due to the spoilage of finished wine. Acetic acid bacteria, such as those from the genera "Acetobacter" and "Gluconobacter" produce high levels of acetic acid. The sensory threshold for acetic acid in wine is >700 mg/L, with concentrations greater than 1.2-1.3 g/L becoming unpleasant. There are different opinions as to what level of volatile acidity is appropriate for higher quality wine. Although too high a concentration is sure to leave an undesirable, 'vinegar' tasting wine, some wine's acetic acid levels are developed to create a more