Although the majority of still white wines are fermented dry to match market demand, many producers are making sweet wines at both the commercial and top end of the market.In the normal vinification process, the yeast converts all the grape sugars to alcohol and CO2 leaving a dry base wine. In cooler countries, notably Germany, some of these wines were perceived as tart and acidic and were sweetened by adding some unfermented grape sugar, known there as 'sussreserve'* giving a light refreshing sweet wine which for many people became their first introduction to the world of wine. This practice continues today
By far the most noble and sought after sweet wines are those made from concentrating the sugar in the grapes giving a natural and luscious sweetness with beautiful acid balance. This process is further enhanced when, in certain regions e.g. Sauternes, and given favourable climatic conditions, the grapes become 'infected' with the fungus 'botrytis' or 'noble rot' which shrivels the grapes and concentrates the sugar.
In Germany and Austria some grapes are left on the vines throughout the winter to freeze, with the result that the water in the grapes freezes and the sugars concentrate. Known as 'Eiswein' these are superb wines, rare, difficult to make and very expensive to buy. In Italy, in the Valpolicella region, grapes are laid out on straw mats in aerated warehouses to dry and go on to make the luscious Amarone and Recioto wines.
