High PH in White Wine from Grapes

[Matthew Stahl]

Thank you in advance for anyone willing to lend their knowledge! I have about 10.5 gallons of a mix of Chardonel and Vidal Blanc must that has already gone through primary fermentation (.25 brix at this moment) and racked twice. The must is from crushed/pressed grapes grown in Western PA so I knew there would be high acidity. I did a PH test last night and I am at around 2.8-2.9, which seems extra acidic to me. I do not have the ability to cold stabilize, but I am ordering some Potassium Bicarbonate. The carboys are sitting in my basement at around 66-68 degrees.

My question is - Do you think the Potassium Bicarbonate will do the trick to get me to 3.2 ph? I'd also like to MLF after raising the PH.

 

[Rice_Guy]

* Potassium is the active ingredient (flavor) in light salt so I am hesitant to pull more than 0.1 pH unit with it. It will complex with tartaric and help pull some out but the effect is hard to predict / wine is not as clean a system as distilled water. Calcium carbonate does the same chemistry without the flavor. The down side is it has slow solubility so your effect isn’t instant. , , , yes potassium will raise the pH if you go that route.
* What was your starting pH? , , wine will increase pH back to the starting level once all the CO2 is removed. Yeast does not like less than 3.0 so I will guess that you started higher like 3.1 to 3.2 and what you measure now is CO2.
* Add a malolactic culture.
? ? Patience ? ? You do have time at this point.

Thank you in advance for anyone willing to lend their knowledge! I have about 10.5 gallons of a mix of Chardonel and Vidal Blanc must that has already gone through primary fermentation (.25 brix at this moment) and racked twice. The must is from crushed/pressed grapes grown in Western PA so I knew there would be high acidity. I did a PH test last night and I am at around 2.8-2.9, which seems extra acidic to me. I do not have the ability to cold stabilize, but I am ordering some Potassium Bicarbonate. The carboys are sitting in my basement at around 66-68 degrees.

My question is - Do you think the Potassium Bicarbonate will do the trick to get me to 3.2 ph? I'd also like to MLF after raising the PH.

 

[Matthew Stahl]

Thank you so much! So my starting PH was higher, it was around 3.2 and the fermentation was wonderful with EC1118. It worked very quickly. I am going to add the malo culture (Wyeast 4007), just wasn't sure if I should add it now before any de-acidification process. I do have time, the wine is very young right now, just newer to this and making sure I am doing the right thing.

 

[cmason1957]

Did you get rid of all co2 in your samples before measuring the PH? If not, you want to try to. I believe heating is the way to go. I never measure my PH right after fermentation, so I'm a little unsure of this. Perhaps someone who does may comment and correct me, if I am wrong.

 

[1d10t]

My first rodeo with MLF so I've learned from reading that you MIGHT need to take the pH into account with it. If it is too low to start some strains may go nowhere if your pH is truly that low.

 

[cmason1957]

My first rodeo with MLF so I've learned from reading that you MIGHT need to take the pH into account with it. If it is too low to start some strains may go nowhere if your pH is truly that low.

But you insure that by getting your ph into the correct range prior to fermentation. If you were good then, you are still good. Unless something really went wonky during fermentation.

 

[Matthew Stahl]

Yes, so, I am in a weird spot because the PH was near 3.2 before fermentation (probably closer to 3.3), and now its around that 2.8-2.9 level. So I am thinking whelp I need to raise it to even start MLF. I added no acid to the must as an FYI.

 

[mainshipfred]

It's definitely a style choice but I don't put any of my whites through MLF, in fact I stop it from happening by adding Lysozyme. I made a Sauv Blanc that ended up at 2.9 pH and it is quite nice but again a style choice. Doesn't help with your MLB dilema though.

 

[Matthew Stahl]

Thank you all for your advice!

 

[Matthew Stahl]

As an update, I added minimal amounts of potassium bicarbonate and my PH is back up around 3.2. When temperatures drop, I am going to keep these car boys in the cold garage to drop out any junk. I tasted the wine and it’s much less harsh. It doesn’t smell delicious (not sure why) but it’s definitely better balanced.

 

[user 36973]

Late to this thread. My $0.02 is that the pot bicarb is definitely the way to go. But you should be targeting your TA not your pH. And I don't recommend MLF on whites since it tends to dramatically lower fruit flavor which for me is the main feature of a white wine. Another choice of 71B yeast could have lowered your malic during fermentation.

I'd determine your TA and shoot for like 6.8 if you're planning on a dry wine up to 8.5 if you plan a sweet wine. Do a bench trial on one liter of your wine and make sure the pH stays below 3.5. Then add your sulfites, sorbate and cold stabilize. (If you have a chest freezer and a plastic container, you can toss it in there, depending on the batch size.)

Cold stabilization will drop a lot of the extra potassium you are adding. Wouldn't want to add more than like 2.5g/L though. Calcium carbonate is problematic because it will SLOWLY drop calcium tartrate over the next year. Your cold stabilization will be fast, on the other hand.

 

[Matthew Stahl]

Late to this thread. My $0.02 is that the pot bicarb is definitely the way to go. But you should be targeting your TA not your pH. And I don't recommend MLF on whites since it tends to dramatically lower fruit flavor which for me is the main feature of a white wine. Another choice of 71B yeast could have lowered your malic during fermentation.

I'd determine your TA and shoot for like 6.8 if you're planning on a dry wine up to 8.5 if you plan a sweet wine. Do a bench trial on one liter of your wine and make sure the pH stays below 3.5. Then add your sulfites, sorbate and cold stabilize. (If you have a chest freezer and a plastic container, you can toss it in there, depending on the batch size.)

Cold stabilization will drop a lot of the extra potassium you are adding. Wouldn't want to add more than like 2.5g/L though. Calcium carbonate is problematic because it will SLOWLY drop calcium tartrate over the next year. Your cold stabilization will be fast, on the other hand.

Thanks you! I used k-bicarbonate and it worked very well. My PH is up around 3.2 and it is not extremely tart any more. Cold Stabilization will occur in my garage over the winter so let’s see how it goes!

 

[jvbutter]

so is cold stabilize much better than adding Pot Carb? I understand they both do the same, dropping out Tartaric acid from the whites. We get into the 20's come Dec/Jan. I have moved them outside prevoius years.

 

[cmason1957]

so is cold stabilize much better than adding Pot Carb? I understand they both do the same, dropping out Tartaric acid from the whites. We get into the 20's come Dec/Jan. I have moved them outside prevoius years.

Cold stabilization will not drop out nearly the amount of tartaric as adding pot Carb potentially can. I haven't ever measured the difference after cold stabilization, but I can't imagine it is much more than 0.05 of the pH.

 

[jvbutter]

thanks Cmason. I might do a test this winter. I've about 20g of high acid Riesling. It wasn't a great year.

 

[Stressbaby]

Could have been mentioned earlier, but if you are starting at 3.2, cold stabilization will paradoxically decrease your pH.

 

[jvbutter]

Could have been mentioned earlier, but if you are starting at 3.2, cold stabilization will paradoxically decrease your pH.

that was my understanding, the tartaric acid crystals will drop out, lowering the PH, not increasing it.