Vintners in Austria’s wine making heartland of Burgenland have started harvesting the grapes to make ice wine (Eiswein).
The sweet dessert wine from the region which is now sold around the world is only made from grapes harvested after temperatures fall below freezing and the grapes are completely frozen through.
The sugars and other dissolved solids in the frozen grape do not freeze, but the water does, allowing a more concentrated grape must to be pressed from the frozen grapes, resulting in a smaller amount of more concentrated, very sweet wine.
Eiswein is believed to have originally been discovered by the Romans with written reports recording the harvesting of frozen grapes as long ago as 23 AD, but it seems to have fallen out of practice and was only rediscovered around 1829 when German winemakers discovered that the grapes left on the vine as animal fodder for a particularly hard winter yielded a very sweet must.
Only healthy grapes keep in good shape until the opportunity arises for an ice wine harvest, which in extreme cases can occur after the New Year, on a northern hemisphere calendar. This gives ice wine its characteristic refreshing sweetness balanced by high acidity.
Although a good harvest is lucrative ice wine production is a risky business. It can only be carried out in regions where the cold can be relied upon and if the frost does not come early enough and the grapes rot, then much of the harvest can be lost. Because of the need for cold, in most of France, the climate is too warm for ice wine production.
It is also a very labour-intensive business with the grapes needing to be picked by hand to make sure only clean disease-free grapes are used.
But this year the Auslese (late grape harvest) in Burgenland started this Thursday when it was cold enough for the grapes to be frozen completely through and where vintners have been celebrating the early Auslese, which means less chance for disease to take hold of the grapes and as a result, a good quality wine is expected this year.
Producers are already talking about 100,000 litres of Eiswein from the harvest.
Vintner Hans Nittnaus said: “A good Eiswein grape needs to be healthy with no Botrytis, and they need to be pressed when still frozen. After being plucked the grapes are pressed straight away , providing the ideal conditions for a good year.”
Burgenland’s Agriculture Minister Andreas Liegenfeld (ÖVP) said it was well-known that Burgenland set the standard of quality on the international wine market for great sweet wines with it particularly high in demand in Great Britain, Germany and in Asia.