Ice wine
The sugars and other dissolved solids do not freeze, but the water does, allowing for a more concentrated grape juice to develop.
Only healthy grapes keep in good shape until the opportunity arises for an icewine harvest, which in extreme cases can occur after the New Year, on a northern hemisphere calendar.
Icewine production is risky (the frost may not come at all before the grapes rot or are otherwise lost) and requires the availability of a large enough labour force to pick the whole crop within a few hours, at a moment's notice, on the first morning that is cold enough.
This results in relatively small amounts of ice wine being made worldwide, making icewines generally expensive.
Icewine production is limited to that minority of the world's wine-growing regions where the necessary cold temperatures can be expected to be reached with some regularity.
That winter was harsh and some wine growers had the idea to leave grapes hanging on the vine for use as animal fodder.
[2] There was little effort to systematically produce these wines during this period, and their production was probably the rare result of freak weather conditions.
Inniskillin and Reif lost their entire crop to hungry birds, while Hillebrand and Pelee Island were able to harvest a minuscule amount of frozen grapes.
[12] In contrast to most other wine-producing regions, Canada, particularly the Niagara Peninsula, consistently undergoes freezing in winter and has become the world's largest icewine producer.
[16] However, it is also produced in all other wine growing provinces of Canada, including British Columbia, Quebec, and Nova Scotia.
If the sugar level in the grapes measures less than 35° Brix, then they may not be used for icewine, a minimum considerably higher than that of German Eiswein.
Canadian rules were further tightened in British Columbia in 2000 after a producer dealt with the mild winter of 1999 by moving grapes up to the mountains to seek freezing temperatures.
Cold weather in Gansu province requires the trenching of vines to prevent die-off, but the region has conditions that lead to resilience to rots and is low in industrial pollution.
[22] The most famous (and expensive) icewines are German Eiswein,[23] but icewine is also made in European countries such as Austria, Croatia, Czech Republic, Denmark, France, Georgia, Hungary, Italy, Lithuania, Luxembourg, Moldova, Poland, Romania, Slovakia, Slovenia, Spain, Sweden and Switzerland at least in smaller quantity.
The French language term Vin de glace is part of the wine classification in Luxembourg, but not in France, but is sometimes found on the rare bottles of icewine produced in Alsace.
[24] Because such a small amount can be made each year, it is produced in limited batches and sold only at the cellar door, 3.3 kilometres from Furano Station.
[25] A growing number of wineries near Lake Erie, especially in Pennsylvania, New York, and Ashtabula County, Ohio, also produce icewine.
It may take months to complete the fermentation (compared to days or weeks for regular wines) and special strains of yeasts should be used.
Because of the lower yield of grape musts and the difficulty of processing, icewines are significantly more expensive than table wines.
In other countries, some winemakers use cryoextraction (mechanical freezing) to simulate the effect of a frost and typically do not leave the grapes to hang for extended periods as is done with natural icewines.
German wine law entirely bans post-harvest freezing methods, even if not labeled "Eiswein".
In most years, icewines from Canada generally have higher brix degree (must weight) compared to those from Germany.
