Orangetraube is an white grape varietal, originally selected from wild vines by the influential German viticulturist Johann Phillip Bronner in 1840. Since it's recognition in the "Lexicon der Rebsorten" (Lexicon of Grape Varietals) by August Wilhem von Babo in 1954, it's been cultivated in Germany and Austria, though most frequently as part of a field blend (known in Austria as Gemischter Satz) and rarely as a single-variety wine. When fully ripe, the grapes' skin takes on a slightly orange tint, hence the name Orangetraube, literally translated to "Orange Grape."
Orangetraube has been a part of Zahel's Gemischter Satz field blends since the winery began in 1930, but only since 1966 did Karl Georg Zahel select the variety and isolate it in a single vineyard. He had noticed that the Orangetraube gave his Gemischter Satz a unique quality, and hoped that to highlight the little-known grape in a wine of its own. Two generations later, Zahel is still the only Austrian winery that produces a wine composed of 100% Orangetraube.