High pH

[4score]

Had an interesting experience with our Syrah this season. After crush, the pH was high, around 4.0. We added tartaric acid, doing small additions to our 2 bins, and re-testing. Between both bins, we re-measured around 3.6.

We then began fermentation and followed that with MLF. We are now about 4 weeks into MLF and I took another pH reading only to discover 4.2!! I know MLF can cause a little spike...but my God!

After completing MLF (soon I suppose) and we rack the wine, the plan was to add more tartaric. No, unfortunately I don't know the TA. We're working on that. I understand we should be shooting for 5-6 g/l.

I guess the plan is to adjust to taste. We need to find how much we can add before it turns over-acidic (using samples). Although I really wanted a 3.6 - 3.7 wine, that may involve far too much tartaric add at this post-ferment point. I guess I'd be happy with an acceptable high-pH wine since current measures show it a bit out-of-bounds.

Comments?

What's the reason most winemakers say to apply most of the acid BEFORE fermentation as opposed to post? Additional risk?

Thanks

 

[ibglowin]

Better integration if added before vs post fermentation is the usual reason. I have had some high spikes as well but not in the 4.2 range. Just throwing out the obvious. Check your pH meter, buffers, etc. 3.6 is nice to have but sometimes 3.8 is as good as it gets. Add a bit more SO2 and stick a fork in it. Its nice to have something on hand to blend with if you have it even if its from a previous year.

 

[berrycrush]

I added tartaric acid post fermentation twice and each time I end up with quite a bit of wine diamond sediment. Could that be one reason?

 

[4score]

We're planning to do some acid sampling at pH values of 4.2 (no acid add), 4.0, 3.8 and 3.6. We'll have 4 winemakers there to blind sample. Each of us will try and rank the samples in order of perceived pH. That will be an interesting education! We'll also try to see if we agree on the point where the wine is overly acidic.

Hey, when you have a potentially critical wine event, make a game out of it and chill out!

 

[TonyR]

Have you calabrated your meter?...

 

[4score]

Yes - did a calibration just before the test. Plus, another meter with another sample of the same wine at a second location confirmed the 4.2.

 

[Steve_M]

Our Petite Syrah had high ph readings 3.8-4.0. I too added Tartaric acid reducing it to 3.75, first time dealing with both high ph and Brix did not want to overshoot at all. MLF is underway will retest/adjust when done.

 

[Johnd]

Yes - did a calibration just before the test. Plus, another meter with another sample of the same wine at a second location confirmed the 4.2.

Did you degas the sample before taking your pH readings?

 

[Steve_M]

Did you degas the sample before taking your pH readings?

Which is why I figured I would hold off on retesting, knowing co2 will skew results. It is what it is, I agree what Mike mentioned before get it right before the first pitch is thrown will handle different next year.

 

[Boatboy24]

My Petite Sirah came in at 3.82 (somewhat confirmed by @jgmann67 who got the same grapes and came up w/ 3.81). Added what I thought would get me to 3.7 and let it ride. I'll go by taste from here.

 

[MisterEd]

We then began fermentation and followed that with MLF. We are now about 4 weeks into MLF and I took another pH reading only to discover 4.2!! I know MLF can cause a little spike...but my God!

Thanks

I am presently drinking the vino but if my memory serves me correctly it is normal to see a small jump towards the alkaline side (.4-.5) in pH from pre-ferment to post-ferment.

 

[4score]

Did you degas the sample before taking your pH readings?

No, but that's a good point and we'll make sure we do in the future - and before we add this time post ferment.