To much tartaric

The most recommended procedure is to add all of the chalk to a smaller quantity, stir and react all the chalk and then add this back to the rest of the wine.

The winecalc can calculate acid reduction as well, so if you want to double check your numbers this is a good way (not that I'm saying your numbers are wrong though :)

Jason (Leon?) wrote, concerning calcium carbonate, "The addition will be

2.2grms per litre as the TA is currently 10.2 grm/ltr. and Ph2.9. what method of addition is appropriate i.e. Direct addition of powder, or dissolved in sample of wine before addition etc."

Leon - before you add carbonate you might want to estimate how much tartaric acid will drop out of the wine with cold conditioning. Use several small samples. Add some potassium bitartrate (cream-of-tartar) to half of the samples. Store a set of samples in the frig. for a day or two (mix these several times). Store another set of samples in the freezer. Then, thaw the freezer samples and retest for acid content. You may find a substantial reduction in %TA with the cold treatment.

Also, you probably should test a sample with the amount of carbonate you intend to add to the bulk wine, degass and retest for %TA and pH.

For the bulk wine I transfer to a large container (lots of gas will be released). I add the carbonate directly to the wine in increments with stirring. Make sure the wine is at room temperature (the reaction will be faster and will have a better chance to go to completion). Position a pH meter probe in the wine. Stop when pH rises to a desired point so you don't overshoot. If pH seems OK add all the carbonate salt that your experiments show is needed.

Bill Frazier Olathe, Kansas

fermentation

I strongly recommend that you not use calcium carbonate for deacidification of your wine. Use potassium carbonate instead. The calcium salt will likely leave your wine with a "chalky" taste. Potassium carbonate will not be detectable afterward in the finished wine once you chill the excess bitartrate out.

Also, be sure to try whatever you end up doing on a _small_ volume of the wine first as a reality check. Then when you're satisfied with that scale it up for the entire lot. Watch out for those decimal errors, too! :^/

Tom S

Thankyou all for your valued input.

Leon

deacidification

Leon, If you can chill a sample first, I would do that before anything else. A lot of that tartaric may come right out. If you have already done that, it's best to do a double salt and pull 1/3 of the total wine to be deacidified, adding all to it. It eats the tartaric first then eats some malic if all of the tartaric is gone. That way you will not end up with a high pH malic dominant wine.

That is a whole lot of calcium carbonate, are you sure that is necessary? I would really try chilling first, as cold as you can get it. A fridge is 40 F; 28 is better. That is twice what I would want to use. Potassium Bicarbonate is another option too.

Whatever you do, do it on a sample first.

Regards, Joe