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January 15, 2010

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Tom,

Great piece on ice wine. When we started back in 2000 with our first ice wine, based on my Ontario experience we decided to produce only the classic wine and so adopted the essential elements of the VQA (Vintners Quality Alliance) production standards. These standards are for a natural process and are accepted internationally. Grapes frozen on the vine between -8 and -12C (produce sugars between 36 to 40+brix), then pressed immediately (not storred in a freezer.
Regards, Bob

Bob: I was looking for just such a standard for the States (i.e., 10-18F), but the only one I found from TTB is that grapes must be frozen on the vine. Thanks for the info.

It seems like while a lot of Finger Lakes wineries have "iced" offerings (late harvest fruit frozen after picking), there aren't as many that do the traditional, straight-up ice wine.

Great stuff. Both the coverage, and the icewine :).

I'm squarely in the camp of those enjoying a slight VA edge when it comes to icewine. Looking forward to the followup piece.

Great article on ice wine. Like NY, Michigan makes some great ice wine. I'd recommend an Ice Gewurtztraminer from Bowers Harbor as something different.

As a producer of traditional Icewine, The "iced" or "Vidal Ice" offerings drive me nuts. While these are nice wines, the flavors aren't the same as frozen on the vine, and it causes consumer confusion.


Duncan:
Some of those differences will be addressed in the second part of this series. Stay tuned...

Tom, here are my notes from teaching the WSET Diploma. These are the VQA regulations in Canada and have been adopted by the EU for Ice wine production. Some of my comments are interspersed with tht the notes.
Grapes must be picked frozen without artificial refrigeration until the grapes are pressed.
Grapes must be picked at a minimum of -8 degrees centigrade (17 Degrees F) typically -10 to -13 degrees, below –14 can’t extract any juice.
Take 3 kg of Riesling and 3kg of Vidal to make one 375ml bottle of ice wine . You get 6-7 time less juice than normally picked grapes
Colder the temperature the higher the brix
minimum of 35 degrees brix at harvest
Must be pressed within the VA
RS must be 125g/l no enrichment or sweet reserve is permitted - 100g/l in BC
Grapes must be picked frozen without artificial refrigeration until the grapes are pressed.
Repeated freezing and thawing of grapes causes them to dehydrate and concentrates the sugars and acids and intensifies flavor
Hand picked or machine harvested usually at night
Grapes are destemmed and crushed winery doors are left open to maintain the cold
Water in the juice freezes as ice crystals and only little juice remains to be collected.
Juice is clarified, inoculated and a cool fermentation takes place slowly over several months stopping between 10-12% Alcohol with usually 160g/l of residual sugar. No Malo-lactic fermentation but cold stabilization does take place
Blends of grapes are permitted, but not Vidal with vinifera

Hey,

FWIW, we've never de-stemmed or crushed icewine grapes before pressing. I can't imagine how'd you'd move the grapes from the de-stemmer to the press (normally you pump them, but you can't pump frozen grapes). I suppose if you had a gravity set-up such that your crusher/de-stemmer was over your press, that would work.

I do have to wonder about how all that treatment, even at cold temperatures, would affect the temperature of the grapes.

I'm also not sure about the "6-7 times less juice" than with conventional pressing. We get 140 gal/ton with conventional pressing for whole cluster pressing, and ~80 gal/ton for whole-cluster icewine pressing. We do also lose about 2/3 of the weight (for every 3 tons of grapes we leave in October, we harvest 1 ton in January), so maybe that's how they get the math? 1/2 of 1/3 is 1/6?

Anyway, thanks again for the article, Tom! It's great to see all these comments!

Dave

Dave, Thanks for your feedback. I need to make sure I am accurate with what I'm writing. What I wrote was gleened from tasting with Karl Kaiser as well as the entry in the North American Oxford Companion to Wine edited by Bruce Cass. Perhaps I may have gotten the terminology mixed meaning pressed when I wrote crushed. I'll check my notes that lead to the write up. I'll retweet this and perhaps get a few more ice wine makers to chime in.

Hey mark,

Thanks for your comments, and the reply. I didn't mean to be critical--I was mainly curious (especially about how one would move de-stemmed maybe crushed icewine grapes). I'd heard in other places that people do this, and have never been able to figure it out.

Dave, I checked my notes, it came from the mouth of Karl Kaiser at Inniskilin and is also in their tech sheets on ice wine. I don't know how they do it either. We are a little to warm in SE PA for us to try and if we did it would be vidal.
Mark

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