When is adding tartaric to lower pH a loosing battle?

[Applegrower]

Working with 30 gallons of 2023 Norton. The question is how much total tartaric addition is too much. The soil here is very high in K so pH coming out of mlf is usually high 3's. Having had zero luck lower pH by adding tartaric pre-ferment, this year it wasn't added until after mlf finished (paper chromatography showed no malic and no tartaric) and I was faced with a 4.1pH. At crush the pH was in the 3.5-6 range. To date, three tartaric additions have been made to lower pH: one of 2.0g/l right after mlf, the second of 2.0g/l when the SO2 was added and a third of 1g/l when SO2 was again added. So, 11g/l total.

Currently, SO2 is still low at 19.2 with a pH of 3.80 and abv of 13.1. I'm willing to settle for a marginal free SO2 of 29, but first very much would like to lower the pH more before adding any more SO2. There noticable tartness to the wine at present, so is adding another 2.0g/l tartaric wise? That should take the pH down to 3.60.

 

[winechef]

How's the flavor at 3. 8. I guess you could lower to 3. 6 but if flavor is good, why change it. I'd take 1 liter, and separate into a few different beakers, make an acid solution and then add 1 ml 5 ml 10 ml 15 ml additions of solution into the wine. taste each one, then check the Ph

 

[cmason1957]

If it is already tart, adding more acid (more tartness) probably isn't the best thing to do.

With a Ph of 3.8, the charts I have say your SO2 needs to be higher than it is, 50-80.

Once I am post-ferment taste has to be the overwhelming decision maker.

At a minimum doing a bench test where you lower the Ph and taste has to be foremost. Shooting for magic perfect numbers is a losing game. Particularly with Norton, it always seems to have higher Ph than the books say are perfect for wine.

 

[Applegrower]

Yup, the calculator I use called for SO2 at 49. Have a couple family members who re touchy about SO2 . . .

Another So2 check is due, guess a objective sampling before proceeding is in order while the ferment tank is open.

 

[winemaker81]

Another So2 check is due, guess a objective sampling before proceeding is in order while the ferment tank is open.

Post-fermentation you a subjective tasting. I agree with the previous advice -- the numbers don't mean as much. Rely on your taste buds -- if the wine tastes acidic, then adding more is not a good idea.

 

[Applegrower]

Hey Bryan,
Raleigh? I'm west of you, outside of Troy sharing a road with Uwharrie Mountain National Forest. Know anyone handy with Norton nearby? I used to talk some to Herb McIntyre but it's been years ago that he quit replying.

 

[winemaker81]

Hey Bryan,
Raleigh? I'm west of you, outside of Troy sharing a road with Uwharrie Mountain National Forest. Know anyone handy with Norton nearby? I used to talk some to Herb McIntyre but it's been years ago that he quit replying.

Unfortunately for you, no. I'm in southern Wake County, and everything is Muscadine or Scuppernong.

Everything I buy is Vinifera from CA, or F-A hybrids from SW VA.

 

[rsportsman]

Working with 30 gallons of 2023 Norton. The question is how much total tartaric addition is too much. The soil here is very high in K so pH coming out of mlf is usually high 3's. Having had zero luck lower pH by adding tartaric pre-ferment, this year it wasn't added until after mlf finished (paper chromatography showed no malic and no tartaric) and I was faced with a 4.1pH. At crush the pH was in the 3.5-6 range. To date, three tartaric additions have been made to lower pH: one of 2.0g/l right after mlf, the second of 2.0g/l when the SO2 was added and a third of 1g/l when SO2 was again added. So, 11g/l total.

Currently, SO2 is still low at 19.2 with a pH of 3.80 and abv of 13.1. I'm willing to settle for a marginal free SO2 of 29, but first very much would like to lower the pH more before adding any more SO2. There noticable tartness to the wine at present, so is adding another 2.0g/l tartaric wise? That should take the pH down to 3.60.

Your wine is probably highly buffered (11 g/L tartaric with a pH still at 3.8!), so that the rule of thumb (1 g/L tartaric decreases pH by 0.1) may not be not applicable here. What is your TA right now? If it's already above 10 g/L tartaric you're going to see resistance to pH lowering by any means. And, yes, taste is already telling you you're probably not going to benefit by adding more acid.
Rich at Vinmetrica

 

[Cap Puncher]

If you are worried about spoilage or Brett with high pH, you could use Bactiless/No Brett inside. They will allow you to get away with less free SO2. I use them regularly with high pH wine. Also, higher SO2 in higher pH wine is usually less noticeable. I have done 50-60 free SO2 at bottling on high pH wine with no free SO2 that myself or others noticed in tasting or aroma.

The same amount of SO2 in a pH of 3.5 would definitely be noticeable.

I have a Syrah with pH of 3.95 going and used the above products. I then target more of a 0.4 molecule for S02 (not the standard 0.5 to 0.6molecular for post MLF reds). If in the barrel I go higher free SO2 and let it drop in the barrel and check at topping up.

I know some of the California guys are less concerned with hitting the 0.5-0.6 molecular when they are high pH as well. They are constantly dealing with high pH.

I used to be way more concerned with the proper pH (and still am somewhat) but have definitely been more in the camp of using your palate as your guide, especially in finished wine.

 

[Applegrower]

Cap Puncher - would mind in more detail outlining your use of either Bactiless or No Brett for me? I read the usage info for both, I'm not seeing how the level of SO2 in the wine determines the amount of Bactiless/No Brett to use. Also, after the addition and subsequent racking how to tell/test if the wine is safe going forward.

Since I only make thirty gallons a year I hope the products have a long shelf life given the large (for me) quantity they're available in and cost.