Sweet Wine

Sweet wines, also referred to as dessert wines, are produced to contain both high levels of sugar as well as alcohol. Due to the fact that the natural sugars in wine are sacrificed to produce alcohol during fermentation, the production of sweet wines tends to require additional winemaking in order to retain these, or add more. Adding sugar can take place before fermentation, known as chaptalization, or after in a process called Süssreserve. While natural sugar can be retained through concentration, removing water through either drying or freezing the grapes, or exposing them to the fungal infection Botrytis cinerea, also known as noble rot.

Sweet wines are produced all over the world, with some of the most renowned examples being those from the Sauternes sub-region of Bordeaux, Canadian ice wines and Tokaji from Hungary.

Because many whiskies have naturally sweet flavours, these types of cask are not suited to all styles and are less common in American distilling, for example. As wine casks have in general, the use of sweet wine barrels, particularly Sauternes, has slowly increased since the turn of the 21st century and releases are particularly prevalent from Scotch distillers with highly experimental wood policies, such as Glenmorangie, Bruichladdich and Lochranza. The first ice wine casks were use to age whisky by Canada's Glenora distillery in 2008.