Ice wine (eiswein in Austria and Germany, or the single-word icewine in Canada) is produced from the pressings of frozen grapes.
Germany and Canada are the leading producers of traditional ice wines, but Austria, Switzerland and the United States also produce ice wine.
Traditional ice wines are made by leaving grapes, such as Riesling, Gewürztraminer, Vidal Blanc, Sylvaner and even Cabernet Franc, on the vines until temperatures drop in the vineyard to well below freezing. In Germany, law states that the outside temperature must drop to 19.4˚F (-7˚C) or below, while Canadian law requires the temperature to 17.6˚F (-8˚C) or lower.
Grapes meant for use in producing ice wine dehydrate and concentrate during the winter, going well past their traditional harvest date. Once a deep freeze occurs, the frozen grapes are quickly harvested.
In some countries, such as the US and Canada, grapes are picked at their peak of ripeness and then put into freezers to yield frozen grapes. While this process is a lot more controlled than waiting, and hoping for a deep freeze, these wines cannot legally be called ice wine. Instead, they are often called iced wine or ice box wines.
Hydraulic pressure is then used to crush the grapes while still frozen, resulting in a very small amount of very concentrated sugary substance. Because the water is frozen solid, it is not extracted from the grape in the pressing process. This high sugar extract is then put through fermentation. With all the natural sugar, the fermentation process does convert some of the sugar to alcohol, but much of the sugar remains in the wine. This results in the very sweet ice wine that is bottled.
Ice wine ends up a golden or deep amber color with flavors of apricot, peach, mango, melon or other sweet fruits. And you may detect a nutty smell to it as well. The really nice ice wines tend to be expensive and therefore are commonly found in half-bottles. These wines are typically enjoyed as dessert wines and pair well with cheese. If you get the opportunity, give one a try. Cheers!