Dessert wines are called “dessert” because, obviously, they're sweet. They're served either with dessert or as dessert. The most popular dessert wines are frequently called late harvest wines, because the grapes are left on the vine through late autumn until they are practically bursting with sugar. Because of the high concentration of sugar, not all of it converts to alcohol during fermentation. The result is an extremely sweet wine. Most late harvest wines are produced from grapes that have been affected by a mold called Botrytis cinerea.

The most noble late harvest, Botrytis-affected wines are German Rieslings that say Beerenauslese or Trockenbeerenauslese on the bottle. Others include the French Sauternes and Barsac, and the Hungarian Tokay.

Another popular dessert wine in Canada, Germany, and Austria is eiswein, or icewine. Grapes are left on the vine so long they freeze when winter arrives! The ultra-sweet grapes are picked and pressed before they can thaw, separating out the frozen water and leaving concentrated juice. The yeasts work as hard as they can, but the amount of sugar wears them out, and the resulting wine is beyond decadent.