This area of Canada produces one of the most internationally sought-after products. This product is icewine. Icewine or Eiswein in Germany, is a late-harvest wine made from grapes pressed while frozen. Only three varieties of vinifera grape and Vidal may be used but usually it is made from Vidal and Riesling grapes.
To make Icewine, the grapes are left on the vine until after the first frost hits. These grapes are harvested after being frozen in the vineyard and then, while still frozen, they are pressed. They must be picked early - before 10 a.m. During both of these processes the temperature cannot exceed -8 degrees C. At this temperature (-8 degrees C) the berries will freeze as hard as marbles. While the grape is still in its frozen state, it is pressed and the water is driven out as shards of ice. This leaves a highly concentrated juice, very high in acids, sugars and aromatics.
In Ontario and in Germany, icewine is defined as naturally frozen. This means that here as in Germany, no other method of making icewine is allowed other than the natural method. No artificial freezing method constitutes icewine by definition or label.
In addition to this there are other requirements to make icewine in Ontario, as set out by the Vintners Quality Alliance (VQA)
These include the following:
the finished wine must, must have a Brix of 35 degrees or higher
there must be residual sugar of 125g/litre
a minimum Brix of 32 degrees in the juice after pressing when measured in the fermentation tank. The finished wine must have a Brix of 35 degrees or higher.
the alcohol must derive exclusively from the natural sugars of the grapes
all wines that is labeled as Icewine must be produced by VQA registered growers and wine makers.
The harvest of icewine grapes must start after November 15. Before harvesting, the producer must verify in writing, (by specified form) the following:
a) the temperatures of each individual harvest,
b) the acreage and tonnage of each given crop,
c) the measured Brix level of each must,
d) the harvesting date and time of day, and
e) icewine pressing capacity.
All VQA icewine processors are required to attend a VQA Icewine Standards Seminar each year.
VQA authorities randomly sample and analyze must, juice and wine to ensure the standards are being met.
It is by no accident that Ontario's icewine is among the best in the world. Our summers ensure high sugars in the grapes and our winters ensure a natural icewine harvest. This combined with the standards set by the industry, leave Ontario's Icewine difficult to surpass.