COLD STABILIZING reduces acid in wineses AND helps it to CLEAR.
During January and February the cool climate winemaker needs to cold stabilize his
wines. Cold stabilization reduces some of the acid. If you used Potassium Carbonate to reduce the acid, cold
stabilization is part of the equation and you MUST cold stabilize.
Put glycerin or sufficient alcohol (vodka) in the airlock to prevent freezing.
Place the carboy at 25-30o F for 2 weeks or more. A temperature of 25-30 degrees F is safe temperature for the amateur
winemaker dealing with glass as a container. Transfer your wine to a plastic
PET jug or a primary fermentor for cold stabilizing.
Excess tartrates will precipitate from the wine. This mellows the wine by reducing
the acid. It will help stabilize the wine by preventing these tartrates from settling out after bottling. Rack into
a clean carboy while still cold, adding proper metabisulfite. Top up with wine.
Filter if desired and bottle when
stable. Always rinse bottles with a metabisulfite solution. Drain well. The drainer trees are very nice
for this purpose.
If your climate doesn’t allow conditions for cold
stabilizing, utilize an old refrigerator.
If you can find a vintage model with the icebox in the main interior, cut the bottom
out of the icebox and allow that cold to drop into the refrigerator to obtain the lower
If you live in our northeastern winter climate and are using a garage or
other outbuilding or cellar steps, install a thermometer and keep a log of outside temperatures plus the
temperature of the chosen area for comparison.
It the expected mean overnight is going to be “in the teens”, you’ll appreciate
knowing whether your wine will safe or not.
The sort-of-safe low-end temperature range is 20 degrees F. A safer low end temperature is 25 degrees F.
You may luck out if your carboy is in an area that went to 16-20 degrees F, but
do you have luck? Some winemakers have had two 5-gallon carboys of wine stabilizing side by side and had one
break but not the other!
Super seeding is the use of a mega
dose of tartaric acid at the rate of 4 grams/liter and keeping the wine in agitation for 2-3 hours at
26oF. Without seeding, the cold stabilization (detartration) should be extended for a month or more
rather than weeks. (Crystals from earlier reactions can be ground up with a mortar and pestle and recycled for