I have a persistent haze in a chardonnay, made from frozen juice. The
wine was finished too late to put it out for a cold stabilitzation.
After completing an MLF, I couldn't get rid of a diffuse haze. I
tried bentonite, and then superkleer. When that didn't work, I
thought it might be a protein haze, but pectic enzyme (that I had
initially used, but then repeated, didn't clear the wine at all.

Finally, I put the wine through a filtration, with perfect results.

I then put the carboy in a large refrigerator, hoping to precipitate
out the excess tartaric acid, and the haze came back.

Interestingly, I had a small jug of the wine, left over, that wouldn't
fit in the carboy, and this small jug, in the refrigerator,
crystalized out perfectly, and is clear.

So, I suspect that the new haze is due to micro-crystals of tartaric.
Does anyone have any other ideas? I doubt that this haze will clear
on its own. Should I re-filter? re-fine? I've even allowed the
carboy to warm up a bit, but it hasn't changed, and is diffusely
cloudy.

Any thoughts would be appreciated.

Lee