WINES OF MARKED QUALITY ICEWINE REGULATION
The Wines of Marked Quality Regulation closely control the production of BC VQA Icewine. The key stipulations are that harvesting takes place at temperatures of -8˚C (17.6˚F) or lower, and the pressed grape juice is a minimum of 35 Brix. Artificial refrigeration of grapes, juice, must or wine is strictly prohibited.
Producers must contact the BC Wine Authority to report the time harvesting begins, and to confirm prior reported tonnages and exact areas of vineyard left for Icewine production.
VITICULTURE
Harvest dates: Can be as early as November or as late as February. Producers track weather systems for early warnings of imminent cold weather.
Permitted varietals: All varietals are permitted. The most common are Riesling, Vidal, Ehrenfelser, Pinot Blanc, Pinot Noir, Merlot, Cabernet Franc, and Gewürztraminer, though Zweigelt, Maréchal Foch, Cabernet Sauvignon, Kerner, Lemberger, Oraniensteiner, Gamay Noir, Muscat and Merlot are all used as well.
Viticultural techniques: Most vineyards are netted against predators, particularly birds.
Harvesting method: Principally by hand. Usually takes place during the night or at dawn.
Harvest temperatures: Although regulation states the temperature must be at least -8˚C (17.6˚F), producers often wait for -10˚C (14˚F) or lower before harvesting.
Frequency: The Okanagan Valley and Similkameen Valley are the only areas to regularly experience these cold climatic conditions in British Columbia. When temperatures do not fall enough for Icewine harvests, producers often make Late Harvest wines.
ICEWINE VINIFICATION
The following are general production techniques.
Pressing: The frozen grapes are brought as quickly as possible to the winery where they are pressed. One press cycle can last up to six hours.
Yields: Yields can range from 150 to 300 litres per ton (compared to approximately 600 litres per ton for dry table wines).
Fermentation: Temperatures generally range from 15 to 20˚C over a three- to 12-week period, depending on the Brix and strain of yeast. Fermentation is generally stopped using cold temperatures resulting in alcohol levels between 9 and 12 percent.
Acidification: Icewines can be acidified or deacidified.
Yeast: Icewine is inoculated, generally using strong fermenting yeast such as PDM.
Cold and heat stabilization: Icewines are stabilized before bottling.
Filtration: Generally using an earth and a pad filter, as membrane filters can easily clog.
Bottling: Generally within 6 to 9 months of the harvest.
Ageing potential: Icewines, particularly from Riesling, can age for over 10 years but are often preferred young and fresh.
