Volatile Acidity

I should state for the record that I don't tolerate the alleged VA in these wines, I think they are better for it. The Gaudriole in particular seemed to get a lot more interesting as this aspect increased, and it became so easy to sell that the last few bottles had to be auctioned.

I think it's something that must go well with raw-honey-like sweetness.
 
It's important to note that all wines contain VA as a natural byproduct of fermentation. So when someone says "I don't like VA", they are commenting on a specific, probably high, level of VA. Once bottled, the VA level of a wine will increase in proportion to oxygen availability (either through the cork as dissolved O2 in the wine). So the VA level slowly increases with time. Low levels of VA often improve a wine and provide aromatic lift, while higher levels can smell vinegar-like and taste like pickling spice.
Since VA is by definition "volatile", it can blow off to some extent with aeration. This is one of the reasons why "slow oxygenation" or the "Audouze" method will improve a very old wine.
 
Kevin,

Interesting thought about VA blowing off. Ethyl acetate is pretty volatile, but acetic acid much less so. Do you really lose that much from an open bottle? Will my Musar become sweet?
 
Hey Kevin,
Since we're on this topic, what happens if you bottle a red wine with very low levels of VA (below what a winemaker would want) and 30ppm of free sulpher? Will it ever get past smelling like a barrel sample?
Best, Jim
 
originally posted by SFJoe:
Kevin,

Interesting thought about VA blowing off. Ethyl acetate is pretty volatile, but acetic acid much less so. Do you really lose that much from an open bottle? Will my Musar become sweet?
Click to expand...
In my experience, slow oxygenation helps with the VA on the nose but not much on the palate.
 
originally posted by Florida Jim:
Hey Kevin,
Since we're on this topic, what happens if you bottle a red wine with very low levels of VA (below what a winemaker would want) and 30ppm of free sulpher? Will it ever get past smelling like a barrel sample?
Best, Jim
Click to expand...
Jim,
That basically what we do, but our SO2 level is closer to 20 ppm. If you pick non-shriveled grapes and keep your barrels topped, you end up with a VA of about .6 g/l. These wines will evolve normally.

Young wines can have high VA because their barrels had too much headspace (oxygen availability) or low SO2 in barrel or the grapes were picked post-shrivel and came to the winery with high acetobacter populations.
 
originally posted by Dan McQ:
tally
originally posted by Jeff Grossman:
posts are being counted; visit your profile page to see yours
Click to expand...

Not only posts, but comments. The head spins.
Click to expand...

I went to my profile page but didn't see any counters.
Where are they?
Better yet, can you list the exact links I should hit and in what order?
Best, Jim
 
originally posted by Kevin Harvey:
originally posted by Florida Jim:
Hey Kevin,
Since we're on this topic, what happens if you bottle a red wine with very low levels of VA (below what a winemaker would want) and 30ppm of free sulpher? Will it ever get past smelling like a barrel sample?
Best, Jim
Click to expand...
Jim,
That basically what we do, but our SO2 level is closer to 20 ppm. If you pick non-shriveled grapes and keep your barrels topped, you end up with a VA of about .6 g/l. These wines will evolve normally.

Young wines can have high VA because their barrels had too much headspace (oxygen availability) or low SO2 in barrel or the grapes were picked post-shrivel and came to the winery with high acetobacter populations.
Click to expand...

Okay, but what do you think would happen with a syrah that was bottled at 0.042 g/100mL VA and 30 ppm free sulpher?
I suspect it will take awhile in bottle to stop tasting like a barrel sample - would you think that is right?
Best, Jim
 
originally posted by Florida Jim:

I went to my profile page but didn't see any counters.
Where are they?
Better yet, can you list the exact links I should hit and in what order?
Best, Jim
Click to expand...

Jim,

Click on "Florida Jim" under your post - i.e., "posted by Florida Jim 9-7-2008 11:15am" in your post above - and it shows up there.

You get taken here.


Took me awhile to figure that out.

Dan
 
originally posted by Florida Jim:

Okay, but what do you think would happen with a syrah that was bottled at 0.042 g/100mL VA and 30 ppm free sulpher?
I suspect it will take awhile in bottle to stop tasting like a barrel sample - would you think that is right?
Best, Jim
Click to expand...
I don't think the low VA would impact the "barrel sample-ness" much, but the 30ppm might slow tannin resolution a little bit. Overall, a wine with those parameters should age normally since VA doesn't help a wine age quicker.
 
originally posted by SFJoe:
Kevin,

Interesting thought about VA blowing off. Ethyl acetate is pretty volatile, but acetic acid much less so. Do you really lose that much from an open bottle? Will my Musar become sweet?
Click to expand...

If acetic acid weren't volatile, how would we be able to smell it? FWIW, acetic acid forms a 3:97 azeotrope with water that boils at 76.6C, which isn't much higher than the ethyl acetate:water azeotrope's b.p. of 70.4C. Pretty impressive, huh, and probably explains why we smell it as easily as we do.

Mark Lipton
 
originally posted by Jonathan Loesberg:
I would like to post my fervent thanks for the absence of emoticons. I always prefer English. The absence of post counts, however, will reduce the number of count-puffing, empty posts, one of the great traditions--even if it wasn't an aesthetic target--of Therapy.
Click to expand...
You may be right. Although so far it appears that the great tradition of empty ('empty') posts remains intact.
 
originally posted by MLipton:
originally posted by SFJoe:
Kevin,

Interesting thought about VA blowing off. Ethyl acetate is pretty volatile, but acetic acid much less so. Do you really lose that much from an open bottle? Will my Musar become sweet?
Click to expand...

If acetic acid weren't volatile, how would we be able to smell it? FWIW, acetic acid forms a 3:97 azeotrope with water that boils at 76.6C, which isn't much higher than the ethyl acetate:water azeotrope's b.p. of 70.4C. Pretty impressive, huh, and probably explains why we smell it as easily as we do.

Mark Lipton
Click to expand...
Life is just a good old-fashioned steam distillation, as any wet dog can tell you.
 
originally posted by Arjun Mendiratta:

Speaking of which, I have always loved this little scientific tidbit (apparently more so than most people):

http://www.chemie.de/news/e/58823/
Click to expand...

Cool! I've wondered about that very issue. Perhaps that explains why some people find that the combination of fish oils with red wine produces a 'metallic' flavor.

Mark Lipton
 
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