Reducing acid - one year old wine

Fishhead - Fining generally doesn't alter the acidity. There are some chemicals you can use (usually potassium or calcium carbonate are recommended) but they do also alter the taste of the wine. If your pH reading is accurate, your wine is already rather low in acid (high pH), so I'd be reluctant to do anything to treat the wine further. Aging alone shouldn't alter the acidity, but perhaps what you are interpreting as acidity is something else. Tannins and/or alcohol level also can produce a bit of a "sharp" taste that may come across to some as too much acid. Some fining agents can reduce the tannins. Or you could just let it age; this tends to soften the "sharpness" over time. The other thing that tends to counteract the impression of acidity is sweetness (sugar), but for these types of wine, you probably don't want to sweeten them.

I'd recommend testing the acidity (even if you're not expert at it) and re-checking the pH before you do anything further. If you made these from grapes (not kits), they may just take a year to two to really settle down. Patience is one of a winemaker's most essential tools (not that it's easy to come by . . .)

Doug

I calibrated my PH meter and re-checked everything. I let a glass warm up some, and I think you might be correct.. maybe it is something besides acid. The cabernet was a bit high on the brix. My vino-meter says close to 15% The merlot was normal brix

I lost my acid test kit instructions, I forgot how to determine the acid.. I thought it was the syringe * .25 I measured the color change at pH 8

Cab/merlot blend pH is 3.85

I also checked a blueberry wine that I have been drinking. Which I think is a bit tart

pH is 3.75

Maybe it is just age... I am in no hurry, just want to do it correct. ( I have plenty of beer to drink !)

Could this also be excessive SO2?

I have been adding 1 tablet per gallon whenever I rack... which is 5 times now.

Fishhead wrote:

So what are some suggestions for correcting it?

Good question! I have never found a reliable way. My suspicion is that there is too much of the wrong type of acid. Maybe Lum has a suggestion. This is more up his alley.

Ray

The usual approach is to use tartaric to bring the pH down to about 3.6 and then cold stabilize the hell out of it. I have a Syrah from last year that's at 3.9 and TA about 6.5, so the acidity is actually where I want it. I took a sample bottle and added about 2g/L tartaric to bring the pH down to 3.6, then froze it in the freezer for a week. When I defrosted it and tested, the pH went down to 3.5 and the TA was exactly the same as before - 6.5. So this test indicates that treating this particular wine in this way should fix the pH problem. I would definitely recommend a test though before comitting the whole batch, I hate it when the reds end up too acidic.

Also, back to the sulfite - there is a chance there is too much in the wine, so measure it too. If excessive, sulfite can give harshness to the taste in the back of your throat, similar to acid.

Pp

I can rack a gallon off and try this process

Is there a standard way to determine how much tartric to add to adjust?

What is the acid level I am shooting for in my merlot/cab blend?

pp wrote:

Not really. The common method is to make up a strong solution of tartaric acid in water and then add a small measured amount (pipette or syringe) into a sample of wine, say 1 litre. Then measure the pH and repeat until the level gets to where you want it, say around 3.6-3.65. Then from the amount of solution and size of the sample you can calculate how much acid you've added in terms of g/L and from that you can easily get the total amount for the whole batch.

Do the full test (including stabilization) for the sample and then adjust based on the results. For example, in my case I've added 2g/L of acid and the pH went lower in the end then I wanted, so I'd probably add only about 1.5g/L to the full batch.

Also, I'm not sure how instant the pH change is after addition and mixing, so it's probably better to remeasure the pH on the test sample next day to get better data.

I would go by taste at this stage, numbers can be misleading. And you won't know where the TA will end in the end because it will be pretty high before cold stabilization and that process is pretty unpredictable.

Also, I haven't decided myself if I'm doing the adjustment on the whole batch because I can't get reliably get the wine to the 25F or so needed for a thorough cold stabilization. My current thinking is I'll do 3 gallons in the interest of "research" and leave the rest (6 gallons) alone for now.

Pp

That's an incredible amount of SO2, it's probably the issue. You have added 5 times too much several times too many as I see it.

It's my understanding that 1 tablet per gallon equals around 100 PPM, I ony add 20 PPM per rack and rack 3 times or less as a rule.

You can get titrettes to measure this, other ways like vacuum aspiration are better but pretty costly. Just use the color of the foam in the titrettes as an indication of change (end point).

If your acid test results are correct it's not that high, contact the people you bought it from to determine if your process is correct.

High pH is an issue, but 3.85 is actually not out of the question. Technically it's too high but I have had them last 5 years. If anything they age quickly.

If it's too much sulfite, I would see how much it is and go from there. I would calculate this as about 400 PPM if you let things splash when you rack and that is 6 to 8 times too much. Blending with this years wine may be the best option if that is the case.

Joe

You can send a sample to Vinquiry and they will do an AO Free SO2 test for $12.00 If you have a fair amount of wine and do not have AO test equipment of your own you may wish to consider this. AO is suppose to be superior to Ripper method for free SO2 determinations. Vinquiry will send you sample bottles free of charge.

Thanks I only have a few 5 gal batches. I am going to try to test this myself

According to Ben's SO2 article, it's a bit lower - 67ppm for potassium based tablets or 78ppm for sodium. But it's still way too much. At that level, it should be plainly noticeable by smelling alone, even without titrets.

Also, titrets are good only if the level is < 100ppm, otherwise the measurement is off the scale. If that happens, you can always dilute the sample to a 1:1 or 1:2 ratio with distilled water and then measure that.

Pp