Out of whack PH/TA readings...

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Siwash

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I recently posted on a Cab Sauv - Syrah blend (80% Cab) that I made last year (autumn 2015). I did not perform a MLF. The flavour is "off" - hard to describe.. could be the presence of high levels of malice acid? Anyhow my Vinmetirca readigs indicate that this wine is off - PH is 4.05 and the TA is 7.5 - odd that both are high as I figured that the PH would be low with a high TA but I am venturing to guess that the presence of malic acid is causing this odd reading and the off flavors

I added oak staves to it on Dec 1 hoping that the oak would mellow the wine.

What about other techniques at this late stage? Given that it is a finished wine for all intents and purposes, what else can I do to improves this wine? I made 27 gallons of the stuff sitting in demis! Hoping to save it!

What about "cold storage"? Ive read that this can bring acids in line? Is this accurate? I don't want to add tartaric acid at this point since the TA is big already at 7.5

The silver lining is that my 2016 wine is MUCH better as I did an MLF and I have made ajustmetns over the past several weeks.. plus I and the advantage of finally using a Vinmetrica.

Any help would be most appreciated!!:h
 
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Agree with @NorCal on the bench trials with tartaric.

You really need to try to get your pH down, despite the fact that it will increase your TA. At 4, concern over stability is a real one, as it takes a boatload of kms to protect the wine. The high ph also contributes to color loss and increases the difficulty of aging gracefully.

Please research this, but I recall that one of the two chemicals we use to remove acid from wine acts upon both tartaric and malic acid equally, I think it's sodium bicarbonate. If you could treat the wine and have it dump some tartaric and malic, then come back and add tartaric to get your ph in line, you may be able to rid it of some of the the sharper and more tart malic. I do not know if this will work in practice.

Cold stabilization wouldn't seem to me to help here, you'll just dump tartaric, raise the pH further, although the TA will go down, you'll still have a ph problem.

Sorry, I'm kinda thinking out loud here...........
 
If you didn't do ML, then I agree with the others on the issue likely being high malic acid. Deacidification of a small amount of wine and adding it back to the main batch is possible, but I have never done this so I cant comment much.
You may still want to run a bench trial dropping the ph to 3.6 with tartaric and then doing an overnight freeze, thaw and decant the wine, then bring back to room temp and re-test ph and TA. If the wine is high in potassium, it is possible that more tartaric will drop than what was required to bring it to a 3.6 ph.
 
Ok thanks guys... will try a bench trial with some tartaric and see where that takes me...
 
how much of a bench sample should I use? a gallon? more?

Use an amount that you can then take your bench trials and apply it to the whole. I like easy numbers like 100 ml, 500 ml, 1 L...750 ml works too but then I need to invoke a calculator when figuring how much to apply to the rest of the batch.
 
I use 100ml. Enough for a good taste and makes the math easy. If you find something you like, walk away and try to do it blind, to make sure it's what you want to do. I did .5, 1, 1.5 g per liter trials. All were undrinkable to me. Settled on .2, and it made a difference.

What is funny is that you can add 5 g/l tartaric pre ferment, but just the smallest amount changes the taste of finished wine. Anyone know the chemistry of why that is?
 
When you add acid pre ferment a significant amount drops out once the alcohol is produced and the solubility of bitartrate drops. When adding small acid additions post ferment, you have to give some time for the acid to combine and mellow before tasting. With larger additions you should chill proof or at least cellar for some time to allow acid to drop out due to changing the bitartrate equilibrium. When the tartrates drop out the tart taste is reduced. I have made several tartaric additions post ferment throughout the years, and every time my neighbor would taste and say the wine was "gone", too tart, and every time massive precipitation of tartrates would occur during several months in the cellar, and the wine would finally meet his approval.
 
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