Under the so-called 'Federweißen'one understands the still imperfect fermented grape must. It is offered with an alcohol content of ca 4to 5% but can have up to 10% alcohol with proceeding fermentation. The still existing yeast cells distribute to the must a cloudy appearance and are significantly responsible for the name because the swirling yeast cells look like small white feathers during the fermenting process. The Federweiße is also know as "Rauscher", "Bitzler", "Bremser", "Krätzer", "Sauser", "Suser", "Sturm" or "Neuer Wein" at other regions (not to confuse with the "Primeur"!).

The phase of the wearing off fermentation, when the Federweiße loses it sweet taste, the fructose of the grapes has fermented through the yeast but not yet totally to alcohol and carbonic acid lasts only a few days. The fermentation process can be prolonged through cool storage; in the fridge for instance will theFederweiße last for ca 10 days.

With according treatment and storage the Federweiße would develop after the finished fermentation process into wine. Therefore the Federweißer is not produced as special beverage but as an early product of wine producing. That's why theFederweiße is only available for a short period of time after the vintage depending on the growing region and harvest. The grape-harvest starts in the Rhein-Lahn-District at the end of August. Federweißer is mostly offered made from white grapes, but can also be won from red grapes.

Federweißer is rich in vitamins(vitamin B1 and B2) and has a purging quality. But be careful: its sweetness and sparkling, tingling taste seduces one to drink easily one glass too many.That is why the Federweißer istraditionally served with fatty foods like onion quiche, bacon quiche or liver sausage with jacket potatoes and butter.