Question: Volatile acids

What are volatile acids? Are they only considered a bad thing?

Please don't take this as a rebuke, but if you google for "volatile acidity" you'll see some pretty good information comes up high in the list. Why not take a look at some of these links first and come back if you need any clarification.

[David M. Bueker]

Volatile acids are the results of acetobacter in the wine. It's essentially the beginnings of vinegar. Almost always a flaw, but a few notable wines have some volatile acidity & seem to get by with it (e.g. Turley Zins), though I find virtually any trace of VA (the common abbreviation) to be unbearable.

In wine VA is bad. Acidity is an important part of wine, but when the acids become volatile, it is an undesired characteristic. Just think of the definition of volatile, then apply that to anything.
Most commonly used when there is too much acetic acid in the wine - acetic acid is the acid of vinegar.
Wine wants good acids - malic, lactic, tartaric, citric, succinic, for example. They are fixed acids.
VA can get into the wine through rotten grapes in the first place or bad winemaking. It is not a fixed acid and this is why you can smell it as it vaporises - like vinegar or acetone (think nail polish remover) or something like that.

What are volatile acids? Are they only considered a bad thing?

Typically, it's acetic acid (vinegar) or ethyl acetate. While it is generally considered a fault, there are exeptions:

"The late Max Schubert, the celebrated maker and creater of Australia's greatest red wine, Penfolds Grange, deliberately induced higher levels of volatility in Grange by leavings the bungs loose in the casks in the first year of the life of the wine. He argued that the very high levels of extract, the strengths of the fruit flavor from the low-yielding vines, the strong new American oak influence and the high tannin levels neededto be cut by a certain deagree of volatility to prevent the flavor from cloying. One of his three most celebrated vintages, the 1971 (the others being 1953 and 1955), trembled on the brink: its level was a the legal limit, and -- according to the taster and the occasion -- it either lifted the wine to the very hights or plunged it into an abyss."

-- James Halliday & Hugh Johnson, The Art and Science of Wine (Firefly Books, 2007), p. 211

Just about everything posted is correct. Let me add that volatile acidity is a technical flaw after it passes a certain threshold. In the US the TTb regs allow a certain level of va in wine.

Just about everything posted is correct. Let me add that volatile acidity is a technical flaw after it passes a certain threshold. In the US the TTb regs allow a certain level of va in wine.

Because it is a flaw only after a certain threshold (like brett) is the reason why I don't want to categorise it as a flaw. So what should we call it? A potential flaw? But even that seems to have too negative a connotation for us Madeira + Musar freaks!

-O-

Just about everything posted is correct.

Er, well, just about.

VA strictly speaking refers to acids that are volatile. In practice, in wine this means, acetic acid, what you get in vineger. Most other acids in wine will form solid if the wine is evaporated, but VAs will evaporate - hence the name.

Sometimes you will smell vineger, but more usually you will smell ethyl acetate. This is not VA really, but the result of the acetic acid reacting with the ethanol. So the term VA is also used informally to cover ethyl acetate. That has the smell of nail VARNISH (not the remover, which is acetone), or "Airfix glue" - a clear glue used for plastic model aircraft.

I wouldn't want every wine to smell like this, but I am a big fan of Chateau Musar which nearly always has this character. This wine tends to split opinion, but there are many that would agree with me. You also apparently tend to find it on Peidmonte wines. Can't say I have noticed, but maybe that is why I lik ethose wines too...?

it is common to say that small amounts of acetic acid add coomplexity to a wine and often aromatic interest as well. the problem is, of course, controlling the amount. many famous wines have had it - Grange has been mentioned and the old Caymus Reserve CS can be added. the latter probably had too much though you could hardly tell the press or its purchasers at the time. Often ice wine has way too much. BUT the big thing is that like all flaws, the threshold levels for detecting it and finding it offensive vary considerably. so, people have merrily bought caymus reserve and ice wines all along and will continue.

Excellent reply Thomas, I think the legal limits in the US are 1.2 g/L in white wines and 1.4 g/L in red wines.

Salute

Just about everything posted is correct. Let me add that volatile acidity is a technical flaw after it passes a certain threshold. In the US the TTb regs allow a certain level of va in wine.

Because it is a flaw only after a certain threshold (like brett) is the reason why I don't want to categorise it as a flaw. So what should we call it? A potential flaw? But even that seems to have too negative a connotation for us Madeira + Musar freaks!

-O-

Otto,

That's exactly why I call it a technical flaw. I'm not a fan of va in wine when it has reached the acetate stage, but some people are ok with that.
If, however, it's measured level exceeds what the industry and government has deterimined a flaw...it is a technical flaw.

To me, a wine is flawed whenever some component manages to steal the show, take center stage, mess with the balance. But that's my personal sense of the flaw, not a technical, measurable flaw.

That's why guys like you love Musar and guys like I can take it or leave it.

Just about everything posted is correct.

Er, well, just about.

VA strictly speaking refers to acids that are volatile. In practice, in wine this means, acetic acid, what you get in vineger. Most other acids in wine will form solid if the wine is evaporated, but VAs will evaporate - hence the name.

Sometimes you will smell vineger, but more usually you will smell ethyl acetate. This is not VA really, but the result of the acetic acid reacting with the ethanol. So the term VA is also used informally to cover ethyl acetate. That has the smell of nail VARNISH (not the remover, which is acetone), or "Airfix glue" - a clear glue used for plastic model aircraft.

Er .. wasn't that what I kind of said. I have smelt an almost acetone character in some disgustingly VA'ed wines.
Anyway nail polish / model air plane glue - that on its own tells us something about each other.

Cheers,
Sue

That has the smell of nail VARNISH (not the remover, which is acetone), or "Airfix glue" - a clear glue used for plastic model aircraft.

Er .. wasn't that what I kind of said. I have smelt an almost acetone character in some disgustingly VA'ed wines.

And I didn't say you said it

TBH it was a reference to your post and I realised I had misread your post immediately after I hit submit. But on reflection I thought my comment stood OK in it's own right. I think a lot of people do mix up the smells of nail polish and remover. Well, blokes at least. OK, I'm talking about myself.

Count me as a bloke who probably mixes up those smells.

Between Musar and maybe some old-school Nebbiolo, it's not uncommon to find noticable VA in traditionally styled Rioja. Count me as one who doesn't mind a slight hint of VA (a "lifted nose"), but is put off when it reaches the "assault of the acetate" stage.

I think Sue is “spot-on”. Acetic acid which is a VA found in wines is a precursor for other compounds which in too high of a concentration could be detected as a “fault”. (As others have posted), of course in certain wines if the concentrations of these compounds are held in check (and balance) their presence can add a positive aspect. Basically I guess that if one detects a “vinegar” aroma in ones wine at an early stage, very likely sooner or later “varnish” or “nail polish remover” aromas will possibly follow.

Salute