In Germany common name for a partially fermented grape must. The name is probably derived from the yeasty, cloudy, matte white colour. But in the German Dictionary of the Brothers Grimm the following entry can be found: Federweißer; young, still fermenting milky cloudy wine (from the old name Federweiß for "alum", because alum was added to the wine as a preservative in the past). It was not until the 1990s that a Federrot made mainly from the grape varieties Blauer Portugieser, Frühburgunder and Dornfelder became popular in the Ahr, Pfalz and Rheinhessen growing regions.
Depending on the stage of fermentation, there are numerous designations, most of which are not regulated by wine law. These are Bitzler (Pfalz), Brauser, Bremser, Fiederwäissen (Luxembourg), Prickler, Rauscher, Sauser, Sturm (only in Austria) and Suser. See in this regard also under Must and Grape Must. Complete lists of the numerous vinification measures and cellar techniques, as well as the types of wine, sparkling wine and distillate regulated by wine law are included under the keyword vinification. Comprehensive information on wine law can be found under the keyword wine law.