Huh... never seen that before

[RonObvious]

Both buckets of Marquette did a strange thing this year - As I was racking them after primary fermentation, I noticed they both threw off what look like tartrate crystals on the sides of the buckets. Quite a lot of it, actually. Even stranger, one yeast appeared to throw more crystals than the other. I used RC212 in one bucket and Premier Cuvee in the other. The RC212 batch produced a moderate amount of larger crystals on the sides of the bucket. The Premier Cuvee produced a LOT of fine crystals, to the point that rubbing your hand on the inside of the bucket, you'd swear you were rubbing 60 grit sandpaper. Pain in the neck to wash off, too.

I don't recall ever seeing this happen before, especially with red wine. So far the wine tastes fine, so I guess I'm not too worried. Starting TA was .75 and pH was 4.0. The pH after fermentation was still 4.0. I did not re-check the TA, though I probably should have. I inoculated with MLF when I racked. Wondering if I should add tartaric acid to bring the pH down? Or see where it stands after MLF is complete...?

 

[NorCal]

I'd wait until everything is done and settled and then add acid to taste. Every time I've adjusted a 4.0 wine post ferment to achieve a pH number, I have rendered the wine undrinkable; too acidic due to TA.

 

[RonObvious]

OK thanks NorCal. I hate the idea of having to add acid anyway. I'll probably just let it be what it wants to be. The tartrate crystals still have me scratching my head though. The only thing I did differently was I used OptiRed for the first time ever. I don't see how that could cause the crystals but who knows.

 

[user 36973]

I'd make sure your pH meter is calibrated with fresh standards too. Although your taste buds are the most sensitive instrument in your lab, I find mine can be fooled by excessive amounts of coffee in the morning. The marquette I made this year was running a pH of 3.65 and a TA of 8.0 as it finished fermenting. I haven't remeasured it since it completed MLF last week though. It's heading into the barrels this coming week.

 

[RonObvious]

Yeah, re-calibrating is probably a good suggestion. It has been a while.
It's all the crystals on the sides and bottom of the fermenter that still have me scratching my head. It tastes good so far though, so I guess I'm not going to panic just yet.