Tartrate crystals - soluble or insoluble?

[Cap'n Crunch]

I have heard that tartrate crystals will dissolve back into the wine if the
wine is brought to room temperature. I have also heard that once the acid
perciptates out as tartrate, it becomes insoluble and will not re-dissolve.

Which is it?

Thanks!

[Tom S]

"Cap'n Crunch" <forget...@os.com> wrote in message
news:Nozg9.1458$Qc....@nwrddc01.gnilink.net...

Mostly the latter. KHT _will_ re-dissolve in wine, but you'd have to heat
the wine beyond room temperature. The hysteresis of the system prevents
much of it from re-dissolving. Once it loses its heat of crystallization,
you have to dump heat back into it to make it dissolve again.

Tom S

[MacDonald]

Potassium tartrate or tartaric acid crystals? Either will can dissolve
back in, but slowly. But you would prefer to replace the potassium salt
with tartaric acid, which is slightly more soluble. It would take some
stirring to get it back into solution. When adding tartaric acid to
wine that is low in acid, or to displace potassium bitartrate, I simply
pull about 750 ml from a 5 gal. carboy and microwave it to about 100
degrees. The acid stirs right into solution and then this gets added
back to the carboy with constant stirring.

glen