The first Icewine (EisweIn) is believed to have been made in Germany in the late 1700s when freezing weather struck before the grape crop could be harvested. The winemaker persisted, harvesting and pressing the frozen grapes and fermenting the juice to a sweet wine. Germany and Austria continue to produce Eiswein but their moderate European winters do not always provide the cold weather needed to freeze the grapes.
German immigrants to Canada carried on the tradition of Eiswein in their new country, with Icewine being made in British Columbia and Ontario beginning in the 1970s. With almost ideal climate conditions for the reliable production of Icewine – warm summers to ripen the grapes and cold but not too cold winters – Ontario is now a leading Icewine producer and has earned global acclaim for its Icewines.
Icewine is a unique sweet wine made from grapes that have been left to freeze naturally on the vine. Pressed while still frozen, the grapes yield a sweet concentrated juice that is highly flavourful.
How Icewine is Made
In preparation for Icewine season, the grape vines are netted in the autumn when the grapes are ripening to protect them from being devoured by birds. In November, the grapes must be registered with VQA Ontario inspectors and the grape variety, acreage and estimated tonnage is verified. The grapes are then left on the vine until a sustained temperature of minus 8 degrees Celsius or lower is reached. Depending on the season, this could happen anytime from December to February. During the time between the end of the growing season and harvest, the grapes dehydrate and the juices are concentrated and develop the characteristic complexity of Icewine.
During Icewine season, wineries and grape growers keep a careful watch on the weather forecast looking for an optimum stretch of temperatures between -10 and -12 °C. This temperature range will produce juice in the range of 35 to 39 ° Brix (roughly equivalent to the percent sugar in the juice). Typically, a period of at least 6 hours is needed to harvest and press the grapes – and it is usually an overnight job. Most small and medium sized wineries harvest by hand, often with volunteers who are enthusiastic Icewine lovers and want to experience the harvest first hand. Warm clothing is required. Mechanized harvesting has been developed very recently and is now an option for larger vineyards.
Once the grapes are harvested, they are pressed in small hydraulic presses under much higher pressure than normal for grapes harvested in the regular season. Because the grapes are frozen, most of the mass is water, and is left behind as ice in the press. Only a small amount of concentrated juice is extracted. Juice yields for Icewine grapes are much lower than for table wines – with average yields of 500 litres for each acre netted, or approximately 15% of the expected yield for grapes harvested for table wines. This reflects both the losses in grape volume from dehydration while the grapes hang and losses to hungry birds and other animals.
Icewine juice is very sweet and can be difficult to ferment. High sugars can create a hostile environment for the yeast and fermentation stops early, leaving relatively low alcohol and high sugar levels in the finished wine.
Wine character and style
Icewines exhibit rich aromas and flavours of ripe tropical fruits such as lychee, papaya and pinapple. They are sweet but have a firm backbone of acidity that makes them perfectly balanced, not cloying on the palate. Icewines are often enjoyed with desserts or on their own for dessert but also make a perfect complement for rich savoury foods such as foie gras or aged blue cheeses. Icewine is also used as a “dosage” for Sparkling Wine and as a flavourful addition to cocktails.