When the charms of deep winter begin to run thin, at least we can thank the cold for bringing us ice wine.

Made from naturally frozen grapes that have been left on the vine far into winter, ice wine is one of winter’s most warming—and spirit-lifting—offerings. Here’s what you need to know before you pour your new favorite winter wine.

(Above photo credit: Flickr/cjsingh06)

The History of Ice Wine

Ice wine, or eiswein, as the category is known in Germany and Austria, made its modern era debut in the late-18th century or mid-19th century, depending on whom you ask. Either way, its origin story involves an unexpectedly harsh winter and a vintner who wanted to make the most of his frozen grapes—making liquid gold from proverbial lemons.

How Ice wine Is Made

The sweet, low-alcohol wine is traditionally made from very ripe, frozen grapes in Canada, Germany, Austria, the Finger Lakes region of New York State, and Northern Michigan. Workers, often among the vines in the dark or early dawn, wear gloves to protect their hands from the cold as they pick. When the grapes are pressed, the sweet, high-acid, and concentrated juice is separated from the ice formed by its water content. The ice is discarded, and the remaining  juice goes to make ice wine, resulting in a wine that is “super sweet, super flavored and super pure,” said Lisa Perrotti-Brown, a master of wine and editor-in-chief of Robert Parker Wine Advocate.

“Essentially, freezing the grapes is all about taking a good proportion of the water content out of them, thereby concentrating all the other components. So, what the winemaker has left to work with is pure grape with the volume turned way up,” she said.

Some ice wine makers, namely those based in climates that aren’t cold enough for grapes to ice over naturally, take a shortcut, freezing their grapes manually in a commercial freezer after harvesting. But in many regions, the term “ice wine” can only legally be applied to vintages made naturally. United States law, for instance, stipulates the term only applies to wine made from grapes frozen pre-harvest, and in Canada, ice wine must be made from grapes picked off the vine at or below -8 Celsius (17.6 degrees Fahrenheit).

Why all the fuss? The big difference, Perrotti-Brown explained, lies less between the two processes than the types of grapes used, where they come from, and how they’re grown.

“If we’re talking about naturally-produced ice wine from certain parts of Germany or Canada, then these will largely be high-quality varieties, ideally suited to the climate and left to ripen on the vine far beyond the limits of a normal growing season,” explained Perotti-Brown. “This results in very intense, better balanced, and ultimately more complex wines.”

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