The process of drying grapes out is the same as the process of making green grapes into raisins. During the drying out process the water evaporates out of the grapes leaving grapes that are raisined and have concentrated sugar levels. As the resulting grapes are mainly sugar, with flavour-producing compounds, they result in a very thick liquid that is to be fermented into wine. The resulting wine is a wine with very high levels of residual sugar.
In the drying process the grapes not only concentrate the sugars but also the flavour-producing compounds. The wines produced will have a range of flavours specific to dried-fruit wines. These classic aromas are reminiscent of dried mango and apricots as well as candied orange rind.
Generally speaking the wines that are made in this style will not have 100% raisined grapes, as this would produce a paste that would not ferment. It will be a blend of raisined grapes and fully ripe grapes, which add water, allowing for a thick liquid versus a paste.
There are many fantastic wines produced by drying out grapes across Europe, mainly in Greece and Italy. Some of the most famous examples come from the regions of Jurancon in France, Pedro Ximinez Sherries of Spain and Recitio della Valpolicella in northern Italy.