High pH and TA

[TurdFurguson]

I recently racked my wine (Merlot) after about 3 weeks in the secondary. According to the hydrometer, fermentation is done.

I snagged a pH meter from work and used my acid kit to measure TA. I came up with .625% - .65%. I keep going slightly over when adding the NaOH, but I'm pretty certain I'm in that range. I double checked with the color change method and got similar results.

When I used the meter to measure the pH of the wine, I got 3.98. This meter only had 7.01 solution to calibrate with, so maybe it's off. It tastes a bit acidic to me. I don't want to add tartaric to bring the pH down since that will bump the TA up. Should I be concerned with this? I did not do MLF and I have not added any more kmeta. I did see some charts that adjust kmeta based on pH. Is 3.98 too high and why would pH be high with TA also being high? I thought they moved in opposite directions? Should I just age the wine and see how it tastes in a couple months? This was from pressed grapes (California Merlot).

 

[joea132]

I had .76 and 3.98ph on a batch this year. Sometimes it just happens. My ovz last year had high TA and after malo it came back down however I don't remember the numbers. If I remember correctly the ph was high as well. I would malo and make sure you are super clean and sulfite sufficiently. You won't want to let it sit for 10 years in the cellar with a high ph but if you can't adjust it then you might be stuck with what it gave you. Be sure to sulfite after MLF though for sure.

This is a pain for any winemaker. It might not be a bad idea to try to get some low acid grapes to blend. See what your levels come to after malo and consider it. Many places sell frozen musts and sometimes they list the chemistry too. Just don't forget to taste the wine before you adjust or blend. Chemistry is only a guide, taste is King.

 

[TurdFurguson]

Thanks for the reply. I didn't measure anything during my last batch of wine since I was just following along with everyone else. This year I decided to do some reading and follow good practices, but my numbers seemed off.

I think I'll pick up an MLF culture at the shop tomorrow and go that route. Sounds like it takes a couple of months. Do you think I'd be OK during that time without adding more kmeta? I'm not planning to age this wine. I suspect it will be gone before next fall when we press the next batch. We have a big family and lots of friends who like homemade wine (aka free).

I have a 6.5 gallon carboy filled as well as 2 gallon jugs. I think I'll MLF the carboy and then compare results in a few months. I can always blend some of them together later if necessary.

 

[robie]

That pH is high.

I would add some tartaric acid to get pH down, then cold stabilize to remove any excess acid.

Maybe Grapeman can get in on this, but I believe an mlf will raise your pH even more.

 

[joea132]

That pH is high.

I would add some tartaric acid to get pH down, then cold stabilize to remove any excess acid.

Maybe Grapeman can get in on this, but I believe an mlf will raise your pH even more.

Robie good point. It might be prudent to add some tartaric acid and shoot for 3.7ph but try not to get over .75-.8 TA tops.

And you don't want to add a lot of kmeta before you malo. You can add a small amount and get a sulfite resistant bacteria but it'll cost you. VP41 is highly recommended but it's about $40 for enough to do 60 gallons. I haven't seen it in smaller doses.

 

[TurdFurguson]

What's the down side of high pH? Is it just spoilage? I was hesitant to add tartaric since I thought the wine tasted a bit acidic and the TA was in the recommended range.

I was going to hold off on kmeta until I did MLF. The shop near me has WLP675 and also one from Lalvin. Since it can take a couple of months to complete, am I in danger by not adding kmeta? Would dropping the pH help? I contacted White Labs asking about the WLP675. They said it will not affect pH or TA, it will only convert malic to lactic acid.

 

[ibglowin]

The lower the pH the less SO2 you need to protect against bugs, etc. Lower pH wines will thus age longer as well. Its OK to leave the wine without full SO2 protection during MLF. Just add the sulfite as soon as MLF is complete.

I have a Petit Verdot from last year causing me grief as well. It started with high pH and pretty good acid. i added some Tartaric and got the pH down to ~3.8. Sent it through MLF and now the pH is back up to almost 4.00. This thing rocks on the tongue with excellent mouthfeel and acid so I can't add any more so I just have to hit it with a huge dose of sulfite and I will use this wine as a blending wine mostly with some lower pH wines that will round it out.

 

[TurdFurguson]

Stopped by the hobby shop at lunch. No MLF until Friday. They didn't recommend adjusting pH until after MLF and thought the wine would be fine for a couple of months without sulfites while MLF is happening. Guess I'll just add the culture and see how things look / taste at the end of the year.

 

[robie]

Stopped by the hobby shop at lunch. No MLF until Friday. They didn't recommend adjusting pH until after MLF and thought the wine would be fine for a couple of months without sulfites while MLF is happening. Guess I'll just add the culture and see how things look / taste at the end of the year.

With the pH that high, the need for sulfites is very high. Several months with no protection could be an issue.

If you can accurately measure the level of free SO2, I would do it and add just barely enough sulfites to protect it, but not enough to inhibit the MLF. If you can't accurately measure, leave its sulfites where they are until you finish the MLF. You will need to keep this wine topped off during MLF.