Last week we touched on soil considerations for new vineyards, thank you everyone Spencer Connell and Shelley Sharpe for your responses!
This week: Sweets
Name and describe various winemaking methods for achieving wines with residual sugar.
I will add a method that is very much a part of my world—Icewine.
Eiswein is believed to have begun accidentally in Germany in the1700s when freezing weather hit before the harvest was in. Winemakers persisted and pressed the frozen grapes, ending up with a wine intensely sweet. The cold weather freezes the water in the grapes, and when pressed while frozen, the ice crystals are forced out resulting in intensely concentrated sugars.
In Canada, Icewine is a controlled term. Grapes must be registered with Vintners Quality Alliance (VQA) inspectors in November. They are netted and left on the vines until temperatures reach a sustainable -8C. Grape growers and winemakers watch for temperatures to reach -10C - -12C, an ideal temperature the sugars to reach 35 – 39 Brix. Because a sustained low temperature is required, harvest typically begins after sundown and usually takes place between December and February. Small hydraulic presses are used because much higher pressure is required. The expected yield per acre is about 500L, or 15% of the yield for a table wine.
Fermentation can be difficult in a juice with such high concentration of sugars, and the resulting wines are generally lower in alcohol. VQA requires at least 100g/L of residual sugar. The longer the grapes remain on the vine, the more dehydrated they become—creating beautifully complex flavours. If temperatures do not reach the required low before the grapes must be harvested, the resulting wine is labelled as a Late Harvest rather than an Icewine. Many varietals are used for Icewine, most commonly the Vidal hybrid, but Riesling and Cabernet Franc, and Gewurztraminer are frequently seen as well.
If you ever have a chance to participate in an Icewine harvest, do it. Many wineries rely on a small army of people willing to come at a moment’s notice to help, and some provide a large, celebratory dinner at the end of a long night of work.
If you are looking for an opportunity to taste a variety of Icewines with paired foods, go to the annual Niagara Icewine Festival in Ontario.