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Number of corked wines is down, but TCA is still a BIG problem

17 comments

 

The number of corked wines is definitely lower than it used to be. I’d estimate about 1 in every 30 bottles is notably tainted by TCA. It used to be about 1 in every 12 (humans vary widely in their sensory threshold to TCA; I’m about average), so let’s give credit to the cork industry for improved performance.

Wnen I say “1 in every 30 bottles” I mean that 30th wine reeks of mold to the point where I detect it immediately on pulling the cork, in an “Ugh!” reaction that is always unpleasant. However, a new study on the effects of 2,4,6-trichloroanisole (TCA) leads me to worry more about the impact of sub-threshold TCA, which is far more common than overtly corked bottles.

The study acknowledges that TCA has long “been thought [to introduce] off-flavor substances [and] unpleasant smells” in affected wines. That would be the Ugh! factor. But the scientists also found–and this is the key sentence–“that …TCA…inhibits ciliary transduction channels…even at extremely low…concentrations.”

Lots of verbiage here, so let’s break it down.”Ciliary” is the adjectival form of the noun “cilia,” which are short, hairlike outgrowths from cells.  “Transduction” is the transfer of energy from one system to another–in this case, the transfer of olfactory sensations (smells) from the wine to our nose and brain. This energy transference occurs through the cilia in our olfactory neurons; they are the receptors that are stimulated by external odors, which then are passed along to the brain via olfactory nerve channels.

The worrisome aspect of this statement lies in its implications: Even if a wine does not smell overtly moldy or corky, there may still be enough TCA in it (“extremely low concentrations”) for its vinous aromatics to be inhibited or tamped down. This means that the wine will lack a vibrant aroma. If you’re a wine taster, you know that the aroma is possibly more important in judging a wine than anything else. It is certainly the first important signal (other than the color) that the taster receives about the wine (discounting foolishness like the weight of the bottle and length of the cork), and thus is likely to shape the taster’s subsequent [oral/flavor/palate] impressions. A wine whose aroma does not attract the taster’s attention is unlikely to be one he will signal out for praise.

I wonder how many dull, inert wines I review are actually infected with extremely small quantities of TCA, sub-threshold but with a consequent inhibiting effect on the aroma. It’s impossible to know, of course, without sending everything to a laboratory for testing. So my advice to the cork industry is to intensify their efforts to make every cork in the world 100% TCA-free.

P.S. I apologize if you’ve been experiencing access issues the last two days with my blog. My web host has been having huge server problems. Next week, I’m going over to a Linux server which, they say, will make everything faster and more dependable.

  1. Steve,

    James Laube at Wine Spectator has been quite vocal and persistent in calling attention to TCA leading the charge against TCA

  2. STEVE,

    JAMES LAUBE AT WINE SPECTATOR HAS BEEN QUITE VOCAL AND PERSISTENT IN CALLING ATTENTION TO TCA IN DOMESTIC WINES.

    James Laube at Wine Spectator has been quite vocal and persistent in calling attention to TCA in domestic wines.

    Quoting the magazine’s website:

    “Wine Spectator’s Napa office has been tracking the number of ‘corky’ bottles in tastings of California wines since 2005, and the percentage of defective corks in that category has dropped from a high of 9.5 percent in 2007 to a low of 3.7 percent in 2012. The cork industry has a different estimate of cork failure: typically 1 percent to 2 percent.”

    [Link: http://www.winespectator.com/webfeature/show/id/Wine-Flaws-Cork-Taint-and-TCA_3346

    More recently:

    “The number of California wines flawed by apparent cork taint (2,4,6-trichloroanisole, otherwise known as TCA) fell in 2012 to its lowest level since we started informally tracking this controversial issue in 2005.

    Roughly 3.7 percent of the 3,269 cork-sealed wines from California that we tasted in the Wine Spectator office in 2012 were thought to be tainted by a bad cork. . . . That the percentage of TCA-tainted wines in 2012 is the lowest we’ve seen (down from 3.8 percent in 2011; the highest level coming in 2007 at 9.5 percent, or a 1-bottle-per-case average) . . .”

    [Link: http://www.winespectator.com/blogs/show/id/47837

    Laube champions the use of a specific tasting glass when conducting his wine reviews — noted for its ability to heighten the perception of TCA:

    Excerpt from Wine Spectator Online
    (posted February 22, 2005):

    “A Clear Benefit for Wine;
    Of all your wine paraphernalia, don’t overlook [wine] glasses
    — they really make a difference”

    [Link: http://www.winespectator.com/webfeature/show/id/A-Clear-Benefit-for-Wine_2407

    By James Laube

    . . .

    At home, I use Riedel and Spiegelau glasses (which you can easily order online), and to simplify matters I’ve narrowed it down to two — the Vinum Bordeaux and Vinum Chardonnay/Pinot Noir glasses. I’ve yet to find a table wine that didn’t perform well in one or the other.

    But at my office in Napa, for official Wine Spectator blind tastings, I use an old favorite. It’s not very pretty, but it’s effective. It’s a bowl-shaped, stemless glass with a small punt at the bottom, and an indentation for the thumb on the side. It’s called The Wine Taster Glass from a line of stemware known as Les Impitoyables. I always use this glass, and have for decades.

    As best I can remember, I learned about this glass in the early 1980s. . . . Many winemakers, in Bordeaux, Burgundy, the Rhone Valley and California . . . said they preferred it to other stemware because it helped highlight possible defects.

    It was also said that the glass name . . . highlighted . . . flaws such as Brettanomyces, volatile acidity or TCA taint.

    . . . I’ve stuck with the Impitoyable because it has served me well. Part of it is habit and . . . a lot of it is a belief in the value of consistency, using the same glass for every wine, week in, week out.

    When you’re tasting wine, or better yet, critiquing it, you want to eliminate as many variables as possible. . . . you should go into every tasting . . . and . . . use the same glass.

    The Impitoyable . . . does highlight wine aromas better than any glass I’ve used. That’s why I’ve stuck with it for all these years.

  3. RESUBMITTED DUE TO AN EDITING ERROR . . .

    STEVE,

    JAMES LAUBE AT WINE SPECTATOR HAS BEEN QUITE VOCAL AND PERSISTENT IN CALLING ATTENTION TO TCA IN DOMESTIC WINES.

    QUOTING THE MAGAZINE’S WEBSITE:

    “Wine Spectator’s Napa office has been tracking the number of ‘corky’ bottles in tastings of California wines since 2005, and the percentage of defective corks in that category has dropped from a high of 9.5 percent in 2007 to a low of 3.7 percent in 2012. The cork industry has a different estimate of cork failure: typically 1 percent to 2 percent.”

    [ Link: http://www.winespectator.com/webfeature/show/id/Wine-Flaws-Cork-Taint-and-TCA_3346 ]

    MORE RECENTLY:

    “The number of California wines flawed by apparent cork taint (2,4,6-trichloroanisole, otherwise known as TCA) fell in 2012 to its lowest level since we started informally tracking this controversial issue in 2005.

    Roughly 3.7 percent of the 3,269 cork-sealed wines from California that we tasted in the Wine Spectator office in 2012 were thought to be tainted by a bad cork. . . . That the percentage of TCA-tainted wines in 2012 is the lowest we’ve seen (down from 3.8 percent in 2011; the highest level coming in 2007 at 9.5 percent, or a 1-bottle-per-case average) . . .”

    [ Link: http://www.winespectator.com/blogs/show/id/47837 ]

    LAUBE CHAMPIONS THE USE OF A SPECIFIC TASTING GLASS WHEN CONDUCTING HIS WINE REVIEWS — NOTED FOR ITS ABILITY TO HEIGHTEN THE PERCEPTION OF TCA:

    Excerpt from Wine Spectator Online
    (posted February 22, 2005):

    “A Clear Benefit for Wine;
    Of all your wine paraphernalia, don’t overlook [wine] glasses
    – they really make a difference”

    [ Link: http://www.winespectator.com/webfeature/show/id/A-Clear-Benefit-for-Wine_2407 ]

    By James Laube

    . . .
    At home, I use Riedel and Spiegelau glasses (which you can easily order online), and to simplify matters I’ve narrowed it down to two — the Vinum Bordeaux and Vinum Chardonnay/Pinot Noir glasses. I’ve yet to find a table wine that didn’t perform well in one or the other.

    But at my office in Napa, for official Wine Spectator blind tastings, I use an old favorite. It’s not very pretty, but it’s effective. It’s a bowl-shaped, stemless glass with a small punt at the bottom, and an indentation for the thumb on the side. It’s called The Wine Taster Glass from a line of stemware known as Les Impitoyables. I always use this glass, and have for decades.

    As best I can remember, I learned about this glass in the early 1980s. . . . Many winemakers, in Bordeaux, Burgundy, the Rhone Valley and California . . . said they preferred it to other stemware because it helped highlight possible defects.
    It was also said that the glass name . . . highlighted . . . flaws such as Brettanomyces, volatile acidity or TCA taint.

    . . . I’ve stuck with the Impitoyable because it has served me well. Part of it is habit and . . . a lot of it is a belief in the value of consistency, using the same glass for every wine, week in, week out.

    When you’re tasting wine, or better yet, critiquing it, you want to eliminate as many variables as possible. . . . you should go into every tasting . . . and . . . use the same glass.

    The Impitoyable . . . does highlight wine aromas better than any glass I’ve used. That’s why I’ve stuck with it for all these years.

    ROBERT PARKER LIKEWISE USES THE SAME GLASS WHENB CONDUCTING HIS REVIEWS.

    AVAILABLE FROM ONLINE WINE ACCESSORY SELLERS.

    ~~ BOB

  4. Steve,

    Due to human error and a computer glitch while editing my TCA “comment,” please delete the posting “time coded” at 3:12 AM and the second “time coded” at 3:40 AM.

    Please post the comment “time coded” at 3:49 AM.

    Thank you.

    ~~ Bob

  5. I’ve noticed this in older wines.

    In recent tastings, we’ve poured our 2007 pinot noir and our 2009 riesling. While we didn’t have a large amount of distinctly “corked” bottles, we did have quite a few bottles that tasted “off”.

    I personally love cork, and couldn’t imagine opening a nice wine without it. But I would be a fool to deny the negative effects it can contain. Steve, how do you feel about synthetic corks and screw caps on high-end bottles of wine?

  6. Let’s not overlook that the science was conducted on newts, and Gingrich is a notoriously lousy wine taster.

    It’s been my experience that, while TCA is undeniably a problem, flatout lousy wines are the much larger issue.

    I, too, have only an average nose when it comes to TCA detection, though I often find that I can taste its effects. Often, I lick a newt right after, and that seems to work.

  7. My tap water in Oakland smells like it’s effected by TCA. I wonder if there is some reaction with any chlorination that might take place…

  8. The thought of dull nosed wine does make one reconsider alternative closures. It’s almost worse for a winery to have a consumer think that your wine is dull, than tainted. If the wine is tainted, you’re unlucky and can get another chance, but if the wine is dull, chances are the consumer will abandon the brand all together.

  9. Kim: True, but it’s also true that if the consumer doesn’t understand what “tainted” means, they might think that all wines from that brand (or variety) smell that way, and reject them forever.

  10. David Sharp says:

    Having been around the wine industry most of 35 years I’ve always believed that the bigger problem is the wine with a slight (ie – not perceptible as TCA) TCA problem.

    How many consumers over the last 25 years have purchased a wine from a label they’ve never tried and found the wine wanting in aroma and flavor and then decide never to buy that wine again? And how many of those bottles had a slight, undetectable TCA problem? The winery that made those wines just got an unfair review from the consumer.

    I’m fairly sensitive to TCA and I’ve found this problem in about 10-12% of wines I’ve had in the last ten years.It’s not as bad today as it was ten years ago, but it still exists.

  11. I’ve had varying results on TCA while tasting wines. I have judged a few competitions and every now and again some flaw like TCA will show up. The research on it inhibiting olfactory sensors is interesting as I have sniffed some wines that seem like they were strained through a wet dogs hair and others that only hint at the moldy basement. Lately I seem to be tasting off scents and flavors in some whites that have a soapy scent nature. This is actually from the bottle before it even hits a glass. Curious.

  12. Steve,

    You’ve pointed out the “final straw” that tipped me over the edge, never to use cork again. Obvous TCA is bad enough. It’s hard to accept that any industry can put up with such a high percentage of flawed products caused by packaging, which is all corks are. It was the incidence of the below-threshold effects of TCA that really chafed me. About half my TCA-effected wines were as you describe: not obviously smelling of TCA, but stripped of aromatics (my cork supplier was relatively good – “only” about 2% of wines bottled with their corks were ruined).

    Why don’t our cork suppliers replace every bottle of wine that is returned because of bad corks?

    Peter Rosback
    Sineann

  13. Steve,

    New research findings on TCA reported this week:

    “Corked wine can ‘shut down’ the nose”

    Scientists believe corked wine can taste awful because contaminants dampen the nose’s ability to smell.

    [ Link: http://www.bbc.co.uk/news/health-24108094 ]

    “Your bottle of fine corked wine has a bouquet of wet dog? Here’s why”

    Now, researchers have found corked wine may smell so bad because the chemical culprit, rather than producing a yucky odor, actually suppresses the drinker’s sense of smell.

    [ Link: http://www.nbcnews.com/science/your-bottle-fine-corked-wine-have-bouquet-wet-dog-heres-4B11174530 ]

    ~~ Bob

  14. Tom, I’ve experienced that soapiness too. There are anecdotes that suggest detergent from the glasses but you say it’s straight from the bottle. Interesting.

  15. I’ve smelled a soapiness too. At first I thought it was the glass, or someone in the tasting room cleaned the pour spouts with dawn and didn’t rinse them, but no,,,there are compounds that can make the wine taste soapy.

    Also H2S can really dull the aromatics in wine, even if it’s not perceivable as a rotten egg off odor. In lower quantities it can really take a lot of the fruit from the wine.

  16. Jason, thanks for your contribution to the conversation.

  17. Champagne producers are gung ho for Diam corks though there are very few corked Champagnes.
    I was in Alentejo last week at a beautiful Sheraton in Evora. The wine list was packaged in a large cork folder. There were five lists. One was corked.

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