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Old 10-15-2012, 02:19 PM   #1
seanomac
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Oct 2009
Boston
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I just tested the pH of my Merlot with a meter I borrowed. It's coming in at about 3.98-4.00. I didn't have the meter during the crush, but I did check the TA of the must with an acid test. It looked like it was in the correct range, but I have such a hard time with those tests. I always feel that I see a color change and second guess my results.

Anyway, I checked the SG of the juice in the secondary and it has finished fermenting. I also took a small sip and it wasn't very good. I thought it was a bit harsh. Maybe it will improve with age. I didn't sample my Barbera last year until it had sat a few months. This is about 3 weeks old.

I've read you shouldn't make large acid adjustments after fermentation, but also read that a high pH can invite some nasty stuff to take up shop. What would you recommend? Should I add some tartaric acid? I didn't plan to do MLF, only because I didn't last time and it tasted good. Any thoughts?

 
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Old 10-15-2012, 03:44 PM   #2
novalou
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Jun 2012
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You said the TA test was in range. What was the TA number you came up with?

 
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Old 10-15-2012, 05:16 PM   #3
seanomac
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Oct 2009
Boston
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My notes are at home, but I believe it was around .6%, assuming I did the test correctly.

The instructions with my kit said to stop when any color change was seen. Other instructions say the diluted solution may turn slight gray, but you should wait for it to turn a bit green before stopping. I didn't trust my measurement much, but since I thought I was in the ballpark, I didn't adjust the acid before adding the yeast. Also, one of the grape suppliers, who also makes wine, said he has not had to adjust the acidity in any of the Cali grapes he had been using, so I just rolled with it.

I was able to borrow a pH meter from work and tested a sample now that fermentation is over. It read ~4. I'm just reading now that I can also use the meter to measure TA using the same kit (add N2OH until pH is 8.2). I'll try that tonight if they don't repossess the meter.

 
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Old 10-16-2012, 01:13 PM   #4
seanomac
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Oct 2009
Boston
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OK, so I measured the TA last night using the titration method two ways - color change and ph change. I believe I did this correctly and got similar results. Based on the color change method, I came up with a TA of .6%. Using the pH method, I got .625% - .65%. I overshot the first time and went slower on the second attempt. Since both were in the same ballpark, and were close to the color change results, I think I did this correctly.

Everything I read says that .6 - .65 is a good range for red wines. However, they also say the pH should be in the mid-3 range. My meter is reading closer to 4. I don't have calibration solution for 4.01, so maybe that's throwing it off? I just have the 7.01 solution from work that they keep it in. Thoughts? Also, it's been about 2.5 weeks since the press and the fermentation is complete. Would you suggest adding MLF culture or just racking and letting it age. I'm leaning towards racking, adding some kmeta, and letting it sit for a few months before racking one more time.

 
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Old 10-16-2012, 01:47 PM   #5
novalou
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Jun 2012
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Quote:
Originally Posted by seanomac
OK, so I measured the TA last night using the titration method two ways - color change and ph change. I believe I did this correctly and got similar results. Based on the color change method, I came up with a TA of .6%. Using the pH method, I got .625% - .65%. I overshot the first time and went slower on the second attempt. Since both were in the same ballpark, and were close to the color change results, I think I did this correctly.

Everything I read says that .6 - .65 is a good range for red wines. However, they also say the pH should be in the mid-3 range. My meter is reading closer to 4. I don't have calibration solution for 4.01, so maybe that's throwing it off? I just have the 7.01 solution from work that they keep it in. Thoughts? Also, it's been about 2.5 weeks since the press and the fermentation is complete. Would you suggest adding MLF culture or just racking and letting it age. I'm leaning towards racking, adding some kmeta, and letting it sit for a few months before racking one more time.
I may have a chart (I'll find it tonight) that gives k-meta dosages based on PH. So you may throw in some more since the PH is on the high side.

 
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Old 10-16-2012, 03:33 PM   #6
Flycal6
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Sep 2011
, Mid East
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I wouldn't worry about it myself. But if you do add some acid, be careful. When adding after fermentation, a little bit of acid adds a whole lot of pucker.

 
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Old 10-16-2012, 03:58 PM   #7
seanomac
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Oct 2009
Boston
Posts: 21

I think I'll leave it alone and see what time does for me. I found this article on high pH / high TA wines. Looks like my TA is in the correct range, but the higher pH could lead to spoilage. I'm afraid if I add tartaric to bump pH down, I will move TA up and make the wine to acidic tasting. The article says you can move pH alone with phosphoric acid, but I don't think I want to add that. Maybe I just rack it over and add kmeta to protect it.

http://www.washingtonwinemaker.com/b...dity-problems/

 
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Old 10-16-2012, 04:43 PM   #8
WilliamSlayer
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Aug 2012
Glen Burnie, Maryland
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Interesting, because I just tackled this problem with a cider. I decided to bring my ph down from 3.8 to 3.6 using malic acid. I am also doing this post-ferment. My big reasoning behing lowering my ph is my intention to back sweeten. I figure the acid is needed for balance anyway, so I kill two birds with one stone.

 
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Old 10-17-2012, 11:52 PM   #9
novalou
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Jun 2012
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This link has a calculator that recommends SO2 dosages based on PH. http://winemakermag.com/guide/sulfite

 
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Old 10-20-2012, 02:13 PM   #10
WilliamSlayer
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Aug 2012
Glen Burnie, Maryland
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Quote:
Originally Posted by novalou
This link has a calculator that recommends SO2 dosages based on PH. http://winemakermag.com/guide/sulfite
Much appreciated! I can use that quite a bit.

 
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