VA: What is it, and should we like it?

[Rebel Rose]

Volatile acidity is a component that one finds mainly in the aroma, and it ranges from a faintly molasses-like character to acetone.

Definition from Wikipedia:

Acetic acid in wine, often referred to as volatile acidity (VA) or vinegar taint, can be contributed by many wine spoilage yeasts and bacteria. This can be from either a by-product of fermentation, or due to the spoilage of finished wine. Acetic acid bacteria, such as those from the genera Acetobacter and Gluconobacter produce high levels of acetic acid. The sensory threshold for acetic acid is >700 mg/L, with concentrations greater than 1.2-1.3 g/L becoming unpleasant.

There are different opinions as to what level of volatile acidity is appropriate for higher quality wine. Although too high a concentration is sure to leave an undesirable, 'vinegar' tasting wine, some wine's acetic acid levels are developed to create a more 'complex', desirable taste.

However, that's the short version. I like this explanation . . . Volatile Acidity in Wine

I hope all of our members will have questions about VA perception, but I have a few for our resident winemakers . . .

In fact, alcohol is the primary energy source for most of the acetic acid bacteria. So where do these bugs get their alcohol from? It can all start in the vineyard. When the grape is damaged by birds or after being infected with moulds such as Botrytis, the juicy parts of the grape are exposed to the air. The grape skin is home to natural populations of yeasts which ferment the exposed juice producing alcohol. The Acetobacter's then use this alcohol to produce acetic acid. When you crush these sorts of grapes, the resultant juice will have a high viable population of Acetobacter, and also a higher than normal level of acetic acid.

Wouldn't today's high Brix/high alcohol styles be setting themselves up for high VA levels? And in addition, wouldn't aging your wines for up to three years with little or no racking increase the potential for unpleasantly high VA?

Another issue is that people have varying levels of tolerance for VA. When I first started drinking wine, I found it hard to detect--even in Italian varietals which are known to carry pleasantly balsamic levels of VA. In the last few years, however, I have discovered it frequently, and I have tasted some very high end, touted wines that I did not enjoy because of evident VA. One zin in particular, which I purchased to go with our ribeye steaks on Father's Day, was so heavily balsamic it no longer had varietal character. We didn't finish the bottle; on the second day the acetone (fingernail polish remover) smell was so strong I couldn't drink it. My SO, however, rated it "pleasant."

Is this a function of my (ahem) age and changing palate? Or a proliferation of higher Brix picks?

So many questions, so little wine.

[Don Giovanni]

Mary,

People do get confused with the VA in wine ...in an ICE wine the VA will be much higher...this is ok ...I have my source at another location...as I am out sampling berries... nice to see a hot spot to post... some VA is needed to lift the nuances in a wine to a POINT...it's when you get a fruit bomb that reeks of VA with a alc over 15% that you know drink now or drink a bad wine in the future... out and about...again...

your question

Or a proliferation of higher Brix picks?

YES the brix and high alc reaction with the yeasts ...you get higher VA ...also to extract the bacteria that are still at work, some wineries will do a sterile filtration that rips the heart and soul out of a wine...a no win situation...

[Brad Ballinger]

For me, VA (when it's unwanted) comes across as acetone or finger nail polish remover. Not vinegar. I was at a charity event in which a winemaker (I won't mention the name) was pouring her wines. Most of the people in the room -- and everyone else at my table -- were novices.

When she poured her Syrah, the others at my table (all women, if it matters) said that they just didn't like the wine as much as the one before (a Cabernet). I asked them why they didn't like it. They said they couldn't put their finger on it. I then asked them to swirl and smell the wine, and to tell me if they thought it smelled like finger nail polish remover. "You know, it does! That's it!" The alcohol level was also out of balance on the high side, and it burned going down.

[artisanbaker]

I recently hosted an Eisele vineyard tasting where we tasted a 77 Norman Mini Eisele ("garagiste") that was laden with VA. It was the first wine that I had experienced significant VA in, but I was able to see beyond and the fruit was really glorious. I actually rated it very highly. Almost everyone else at the table, including Doug Eisele and Walter Schug, remarked that it was too much and rated it last. Mr. Schug did say that with the right "roast beef" he could drink it!

As the tasting was blind and my notes had been written, I was married to my positive judgement. I am not a very experienced taster and I could not detect this "fault" of sorts but after this experience I think I am better suited to identify VA and assess accordingly.

We did taste, later on, a wine in which Tor Kenward identified acetone. It was one of the 90's era Araujos I think. At any rate, sounds like there are various forms that VA can manifest itself, but I think I would prefer that all of it be filtered out whenever possible.

Edited September 15, 2007 by artisanbaker (log)

[MaxH]

Though wikipedia (and standard written authorities) focus on acetic acid which is common, VA includes a wider range of organic acids. Also they show up indirectly in the smell because they react with alcohol, yielding just the sorts of solvent esters people associate. Experienced tasters I know don't consider VA a gross flaw like TCA (cork taint).

On the other hand, this thread is the first discussion I've seen to actually ask if we should "like it."