The production of ice wine is subject to a number of conditions: The grapes must be naturally frozen and the external temperature must be at least -7 °C. The water contained in the berries crystallizes and only the sugar contained in the grapes binds non-crystallized water and fruit acids. The grapes are pressed so that only sugar-containing extract is obtained. The result is a highly concentrated and sweet wine. The following vine cultivars are used for the production of this wine: Pinot blanc, Pinot gris and Riesling.