Cold Stabilization on a High TA, High pH Wine

Hi All,

I have a red wine that has a high TA (.93) and a pretty high pH (3.7), and I'm thinking of trying cold stabilization or adding potassium carbonate to lower its acidity. However, I have heard that this will raise the pH in wines that have starting pHs above 3.6. I'm considering adding some tartaric acid to bring the wine's pH to below 3.6 before trying cold stabilization and/or a potassium carbonate addition so that it would also then end up lowering the pH along with the TA. However, this is a scary thought, since I would have to lower the TA a considerable amount (especially with a TA upwards of 1.0 after the acid addition), and don't want to drain too much of the wine's flavor in this pursuit.

Does anyone have recommendations as to whether I should go big with the acid addition before the intervention or just bite the bullet with an increase in pH/add extra sulfites for preservation? Also, I don't think my refrigerator will be able to get the wine much below 35 to 40 degrees, and I have a high alcohol wine (15-16%). Would this even be cold enough to precipitate the acid out through cold stabilization?

I read your post wrong and deleted my response.

Has this wine completed a malolactic fermentation? How old is this wine?

Hi Stickman,

It's about 2 months old. I started MLF on it initially, but had trouble completing it (due to my liberal application of sanitizer I think ha). I tried to restart MLF with reinoculation and OptiMalo, but that didn't work, so I'm planning on just killing off the ML bacteria with lysozyme and trying to think through other ways to get rid of some of the acidity so that I can sulfite it and finally sleep well at night ha. Open to any suggestions.

one method is to forget the numbers and go with taste. do bench trials with sugar syrup (two cups sugar to one cup water) to taste. the sugar syrup addition will balance against the acid and not add any sweetness unless so desired.

in future prefementation addition of tartaric acid to get the ph value down is the appropriate response. ph is more important at this stage. once wine is complete multiple cold stabilization or treatment with potassium carbonate will get TA in line . Taste still is the barometer.

Many people don't consider 3.7 a high pH wine, depending on what varietal it is.

Actually, the "tipping point" for cold stabilization is closer to 3.7, although it is not a precise number by many accounts. The tipping point is the pH at which no significant change in pH occurs with cold stabilization. Below the tipping point cold stabilization drives pH down, above it the pH goes up. But when you are close to it not much change occurs, even if you are not at the exact pH. Other factors come into play, but you are probably at very low risk. I deal with a lot of high pH big reds, out of Walla Walla, and they often finish malo at 3.8 to 4.0. I just bring them to 3.7 and chill, and I rarely see them rise much if at all. If you can only get to 35-40 degrees you may have to go 3 weeks or more.

Yes taste is a good thing to consider. If it tastes OK now I'd just go with it, if its too tart then stabilize.

What temperature are you keeping the wine at during the ml? Idealy it would be around 70. If the temp is too low that will stop ml, bit it will restart once it warms up. Also as the pH rises the effectiveness of so2 goes down, so a pH of 3.5 you might need 30 ppm to keep it protected at a pH of 3.8 its going to nned to be 60 ppm+ for the same protection. And that much so2 is going to be noticeable in taste, it will knock down the nose and affect color too.

The alcohol content is high, so ML may not go, or will be very slow. I agree with the others on going with taste.

Thanks everyone for all the input. The wine's pretty tart right now, so it definitely needs some sort of adjustment. I've been keeping it right around 72 degrees. If I go with cold stabilization, do you happen to know if I can use cream of tartar found at the store for seeding or should I order something special? It seems like this should work, but it's a fairly fine powder so I don't know if this would impact it dissolving into the wine rather than precipitating out as crystals?

I've not used it but I hear people have success with store bought cream of tartare. And you don't really want it to dissolve, just stir in gently. The idea is that the crystals themselves become the foundation for further crystal growth. You are in effect, "seeding."

ChrisL, cold stabilization will bring down your Ta. It depends on where you live, here in Pa I just put my carboys in my shed for a month or so in the winter. Sounds like you are making a hearty red, if you are going to add sugar to make it sweet, or semi sweet dont worry about the acid. If you want it dry cold stabilization is it, other than add chemicals. Its a red and needs to age so don't be in a huge hurry to do anything you have LOTS of time.

So if you have a high PH already would it rise further if you do a cold stabilization to reduce the T?

I cold stabilized Frontenac that was from my grapes, the starting Ta was like 1.4 after the winter was over(left 3 6gal carboys in shed all winter) the Ta droped to 7.5 and the Ph was the same or very close. I lost 4 years of notes, a big cup of coffee landed on my laptop.