Sour Grapes: The Acid in Your Wine

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Our bi-monthly wine tasting group met the other day and looked at Russian River Pinot Noir, tasting around 18 wines, including a very good Burgundian ringer. The tasting was packed with about 25 people in attendance. In the first flight there were six wines and four out of the six had noticeably elevated volatile acidities.

Volatile acids consist mainly of acetic acid, which is easily recognized aromatically as vinegar, and, to a lesser extent, ethyl acetate, which smells of nail polish remover. These are important components of wine. In small doses they can lift wines aromatically and make fruit more present in the nose. For example, low-level volatile acidity can elevate a simplistic cherry aroma, adding dimension and depth, creating a backdrop of blackberry, black currant and chocolate.

They can create such aromatic complexity that It can be like going from a one dimensional world to a five dimensional one with a little age of Aquarius thrown into the mix for aromatic complexity. In limited quantities, they are the plastic surgeons of the wine world, and can give the wine an acid lift, making a wine seem fresher, fuller, and more lively

Volatile acids are most important in warm regions where wines seem clumsy without an obvious acidic lift. When they are bad, they are very bad, and when volatile acids get away from the winemaker they ruin a wine and can render it undrinkable.

The smell of vinegar can be so pungent that it almost feels like it is wrenching out our nose hairs by the root. And the smell of ethyl acetate makes a wine seem so chemical that you can feel as if you are being waterboarded in a nail salon (maybe this appeals to some people).

The mouth feel of the wine becomes sour and thin. The tannins of the wine become so bitter-tasting that the experience can be similar to having a root canal performed by a dentist who suffers from acute halitosis.

Wines with greater density or higher sugar or alcohol can balance larger quantities of these acids; think of the classic balance of sweet and sour in Chinese food. Wines such as Port, Sauterne, and Sweet German Wines like Eiswein, Trockenbeernauslese, and Hungarian Tokay can all support larger quantities of volatile acidity than dry wines because of the higher sugar content.

The main culprit in elevated levels of volatile acidity is acetic acid bacteria. Acetic acid bacteria gain a foothold in wine mainly due to winemaker neglect during aging. Because exposure to air fuels their growth it is important that the winemaker tops barrels and tanks, that is, adding wine to fill the vessel so that there is no room for air to enter.

Other than these four wines that had high volatile acidity there was one wine at the tasting that was corked. Corky wine is generally caused by the presence of chloro or bromo anisoles that create a musty, moldy, wet cardboard or damp basement smell. The main culprit is airborne fungi that contaminates corks before they are put into the bottle.

Wineries can also have ambient problems where the corky character is picked up in wines from treated wood products, pesticides, or tainted chlorinated water before it is bottled. Corky wine is the main reason that the French sommelier watches you so closely when he puts the small taste in front of you at the restaurant. If the wine is corked, you can send it back.

It was clear that the wine in the tasting had a very mild corkiness. There was a slight hint of mushroom that was only picked up by the most sensitive tasters in our group, but others were not bothered by it at all. The four wines that exhibited high volatile acidity, however, were really showing it in spades.

Because of the delicate tannin structure of Pinot Noir the volatile acidity of the four wines affected seemed colossal, cheapening the wines and throwing them out of balance. With four wines with high volatile acidity, and one wine corked, one would think that the six wine would be looking pretty good. But sadly the other wine did not have any body and was weedy and boring.

The corked wine was clearly well made and had good density and complexity. And because the corky character was not the fault of the winemaker, I ranked this wine first. Yes, despite a clear flaw the wine was good, and had it not been corked it would have been the hands down winner.

It is here that I must say that I do not like to rank wines or score wines, but prefer to talk about their merits and interest rather than determine which one is better than the other. I will use the hackneyed analogy of the parent who asked which one of his children he prefers; as with wine, my response is that they are all different, and there is no "best."

Our tasting group ranks wine because we feel that the consensus of the group somehow outranks the individual taste, which is a ridiculous idea. We also rate wines because we love to argue with each other about the relative merits of the wines we like. No one likes to argue about wine more than Paul. If Paul played basketball he would be the guy on the other team that was insulting your mother before the game began. He is the guy that is so abusive that you fantasize about giving him a Zidane-style headbutt to the chest (like the French soccer star) when he opens his mouth. Everybody needs a Paul so he can be sure he can stand behind what he says.

Although we had already identified the wine as corked, Paul started his vitriol upon hearing that I had ranked it number one. My logical response was simple: one wine was just plain bad, four wines had such elevated levels of volatile acidity that they were undrinkable, and the last -- although corked -- had depth and complexity, and was well made.

For the most part, the wines that had elevated volatile acidity had this fault when they went to bottle, and thus, it was a conscious choice by the winemaker to put out a bad wine. This particular corked wine, however, was of good quality but had been spoiled by a bad closure, which was no fault of the winemaker. A respectable wine shop will exchange a corked bottle for a good bottle. Wine shops that sell high volatile acid wines should know their wines. Because for many consumers, tasting these wines may be like entering uncharted territory.