Thursday, April 6, 2023

"Waiter, there's a flaw in my wine!"


The other day, I was sitting at my desk staring out the window, sipping a 1982 Chateau Lafite-Rothschild. 

Okay, that's not completely true.  I was staring out the window, but I was day dreaming about sipping an '82 Lafite.  Between imaginary sips, my mind wandered to an odd subject: do most (or many) wine drinkers understand wine flaws? Or do wine drinkers even know what are wine flaws?

I admit, that's an odd combination: Lafite and wine flaws.  Although anything is possible, especially with older wine, it's not likely that you would ever open a bottle of Ch. Lafite-Rothschild and find a flaw.

Still, not long ago, it would not be unusual to find a corked wine, or a wine infected with brettanomyces, or a wine that smelled and tasted more like vinegar than wine. Fortunately, those days are mostly behind us. Technological advances in modern wine making have mostly eliminated flaws.  But flaws still do occur.

So, here are five common flaws you are most likely to encounter (if ever) in today's wines.  In general, the older the wine, the more likely it is to have one or more of these flaws. 

Cork taint -- There was a time, when as much as 10% of the wines tasted at a large wine competition, were corked. 

Let that number sink in.

What other major business would tolerate a 10% failure rate? And yet, the problem with faulty corks continued far too long before the wine cork industry, mainly in Portugal, did something about it. 

The culprit is a chemical called trichloroanisole, or "TCA."  Cork producers believe that corks are infected with TCA during processing.  A faulty cork causes  the wine to smell musty or moldy and TCA mutes the flavor of the wine. 

Today, it is rare to find a corked wine.

Volatile acidity -- This flaw is caused by a bacteria spoilage. VA, or acetic acid, smells like vinegar and it leaves an unpleasant impression in the finish of a wine. The legal accepted level of VA in the United States is 1.4 g/l (grams per liter)in red wine and 1.2 g/l for whites. Europe is 1.2 g/l for still wine and Australia allows for 1.5 g/l. 

That's the regulatory side of wine making. In reality, detectable VA in a wine today, by smell or taste, is rare.

Oxidation -- Too much air mixing with wine causes oxidation, a flaw noticed more in older wines and wine by-the-glass.  An oxidized wine smells musty, like wet cardboard and in older wines that have been exposed to too much air. A clear visual indication of oxidation is  a browning color.  

As a wine ages, some oxidation is acceptable and is considered by some to add complexity to red wine. Sherry is an example of an intentionally oxidized wine.

Hydrogen sulfide -- This flaw, known by it's chemical identifier H2S, is an off smell and taste, like rotten eggs.  All wine contains elemental sulfur, but good wine making will keep it under control.  Still, sulfur dioxide (SO2), may be present in wine and identified as a burnt match smell, while mercaptans, another form of sulfur, smells like burnt rubber or canned asparagus.

There is one more flaw that I've saved until last because not everyone agrees that it is a flaw, or at least they will say that too much brettanomyces is not good but a little is okay.

Brettanomyces -- Few wine flaws cause more controversy than brettanomyces, or "brett," as it is known in wine circles. Brett causes disagreements by those who like a little in their red wine and those who abhor it.  Brett may be present in the winery and is hard to get rid of.  

In wine, brett smells earthy, leathery, metallic.  Brett is historically present in Bordeaux and Rioja red wines.

A final comment about wine flaws.  Not everyone has the same sensitivity to flaws like brett or sulfur.  A well organized wine competition will convene a tasting panel with judge's having different sensitivities.  It's essential to not have all judges on the same panel not be able to detect, or be over-sensitive to a specific flaw. 

Lastly, personal preference is not a wine flaw. Because you don't like the style of wine you just bought or ordered in a restaurant, doesn't mean there is anything technically wrong with the wine. To quote an overused contemporary cliche: you bought the wine, now own it

With a little practice, anyone can learn to identify a flaw in a wine. The trick is to remember what to look for, then store it in your wine memory for future reference. But don't let looking for possible flaws stop you from enjoying the wine experience. 


Next blog: A Chianti for Every Taste

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1 comment:

  1. Less cork taint is due to fewer corks. More corks are aggregated bits of tree bark held in a plastic matrix.
    Cork taint is down a bit. The only LaFitte I’ve had an opportunity to taste was tainted by TCA.
    The “guarantee” cork producers offer is a joke. Since abandoning wood my closure failures are maybe 0.0001%

    Paul Vandenberg
    Paradisos del Sol


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