Beautiful grapes, not so beautiful chemistry...

[joea132]

Me and my partner in crime got 23 lugs of Lanza Old Vine Zinfandel today and crushed. The grapes were sweet and some of the best looking I've seen. We had a successful crush and I started running the numbers. Turns out our pH is 3.7 and we have 25 brix. But our TA is high, in the upper .8's-.9!!!

I took 10mL of wine that had been through a strainer and placed it in a small glass. I then rinsed the syringe and measured out 10 mL of NaOH solution. I slowly added and got a full 10 mL into the wine. It took 12 mL to get to 8.2 pH in this sample. I re-tested and it took 11.5 mL to get to 8.2. After multiplying by .75 I am getting that my wine is anywhere from 8.6-.9% TA!!! The plan is to put as little chemicals as possible in the wine aide from sulfites and the basics. I am planning on fermenting as usual including MLF and putting it through cold stabilization later on to hopefully alleviate the issue. Any opinions or other advice?

 

[Rock]

Hey joe what type of noah are you using?this sounds kind of high for ta

 

[joea132]

0.10 normality, crosby and baker. Bought the new bottle a few months ago. I guess I could check it against the older bottle I had but an expired accuvin test showed the TA around .9 too.

 

[Rock]

did you add distilled water?

 

[joea132]

did you add distilled water?

No and I never have in the past. How and when should I add it in the process?

 

[grapeman]

Was your pH meter calibrated and if so were the reagents fresh? COuld be some error there. I would however love to have those horrible numbers to work with. Try making wine with Frontenac and have a brix of 26, pH 2.95 and TA of about 1.6 or 16 g/L! A wine with those numbers should be a piece of cake.

 

[joea132]

Was your pH meter calibrated and if so were the reagents fresh? COuld be some error there. I would however love to have those horrible numbers to work with. Try making wine with Frontenac and have a brix of 26, pH 2.95 and TA of about 1.6 or 16 g/L! A wine with those numbers should be a piece of cake.

This was with a calibrated meter and fresh reagents. Haha I bet that's a nightmare! I'm hoping that TA comes down with fermentation, MLF, and if need be cold stabilization.

Grapeman, what do you normally do to bring your wine to acceptable levels?

 

[Rock]

I would add tartaric acid to bring your ph down a bit.I use .2N sodium hydroxide 15mls of wine sample 5mls distilled water.add your .2 untill 8.2 what ever you use is your ta .So if you use 7ml=.7

 

[joea132]

I would add tartaric acid to bring your ph down a bit.I use .2N sodium hydroxide 15mls of wine sample 5mls distilled water.add your .2 untill 8.2 what ever you use is your ta .So if you use 7ml=.7

I see but from what I understand and I'm sure Mike can verify, adding distilled water will not affect the reading. I'm reluctant to add tartaric acid because of the already high TA. I don't think that the pH will inhibit the yeast from doing it's job at that level. I think this is going to just end up being whatever it decides to be. I added color pro and then sulfited 6 hours after to kill off wild yeast but I'm trying not to add any additional chemicals after that unless I absolutely have to. It will be interesting to see what happens when I pitch the yeast tomorrow...

 

[ibglowin]

Don't add any tartaric that will decrease pH but increase TA even more. You just have to let them go. pH will rise with fermentation and MLF but TA should decrease. You will need more SO2 down the road due to the high pH.

 

[PCharles]

Interesting

This certainly is an interesting discussion. With the pH at 3.7 it seems like you should be fine.

I look forward to following this thread to see how things work out... a good learning experience. My guess is that grapes from this particular region have always been like this year after year.

With a little bit of luck they will make the best wine you've ever had. I look forwad to following this thread.

Best regards,
Paul

 

[Rock]

I would not worry about your ta until after pf.but work with your ph now make sure your numbers are correct and add the tartaric acid.

 

[joea132]

Don't add any tartaric that will decrease pH but increase TA even more. You just have to let them go. pH will rise with fermentation and MLF but TA should decrease. You will need more SO2 down the road due to the high pH.

This is exactly what I think too. I'm going to see what happens after PF and MLF.

 

[Rock]

Joe,new readings on the Lanza OVZ from Westchester Amateaur winemaking club.Same grapes as yours are reading 3.5ph 25 brixs.

 

[joea132]

Any indication of TA?

 

[Midwest Vintner]

I don't work with grapes, but even though 3.7 pH isn't acidic enough for most, it isn't too far off either. You might just not want to age it longer. I would proceed with it and check acidity after fermentation, then add if necessary. You can use a lower tolerance yeast if you want to keep the abv down.

 

[joea132]

I just got back from M and M. They tested it with 3 different pH meters and found similar readings as I did. pH-3.66, TA-1.12. I'm going to ferment, innoculate with Malo and hope to hell that most of that acid is malic.

Midwest Vintner-I'm not concerned about the ABV really. But you are absolutely right, with this kind of pH I am not going to be able to age it for very long. Thanks for the info.