Ice wine (or icewine, as one wor, or in German, Eiswein) is a type of dessert wine produced from grapes that have been frozen while still on the vine. The sugars and other dissolved solids do not freeze, but the water does, allowing a more concentrated grape must to be pressed from the frozen grapes, resulting in a smaller amount of more concentrated, very sweet wine. With ice wines, the freezing happens before the fermentation, not afterwards. Unlike the grapes from which other dessert wines, such as Sauternes, Tokaji, or Trockenbeerenauslese, are made, ice wine grapes should not be affected by Botrytis cinerea or noble rot. Only healthy grapes keep in good shape until the opportunity arises for an ice wine harvest, which can occur the following calendar year. This gives ice wine its characteristic refreshing sweetness balanced by high acidity. When the grapes are free of Botrytis, they are said to come in "clean".