Wednesday, April 18, 2007

The Great Decanting Experiment – Wine #2

The second wine to be subjected to The Great Decanting Experiment is one that some will argue is inappropriate for decanting. But as I build up the numbers of wines tested for their ability to respond to decanting I am not going to discriminate. After all who knows what wines are improved by decanting? Oh I’m sure many have an opinion, but is it based on actual comparison between decanted and undecanted wine, or just anecdote?

Wine #2: 2002 Trevor Jones Virgin Chardonnay, South Australia ($10.99USD, 375ml), 13.5% alcohol.
As before one bottle was decanted and the other left unopen. After 2 hours and 15 minutes the second bottle was opened and the two wines poured randomly into three marked opaque glasses while I was out of the room.

Glass A: Very aromatic with aromas of lime, peach, pineapple and anise. Mouthfilling with a soft and supple entry. A solid backbone of appealing acidity. Nice wine!

Glass B: Less open than glass A with peach, anise and pineapple and a hint of dustiness. Very similar to glass A on the palate.

Glass C: A little dusty (but not corked). Lemon, peach and anise. On the palate very similar to A and B, perhaps not as fat as glass A.

My opinion: A is the decanted wine.
Reality: Glass C contains the decanted wine, A and B had undecanted wine.

Conclusion: It was very difficult to distinguish between the three glasses of wine. And in the final assessment I was forced to conclude that the decanted wine was in glass A simply because that glass provided more aromatic complexity. Well that’s what the supporters of decanting argue, right? The dusty character detected in glasses B and C was not TCA as the remaining wine tasted on the next evening was sound and without any evidence of being corked.

Score: Wines tested 2, Decanters 0, Non-decanters 0


Marcus said...

Nice experiments.

My own experience makes me inclined to believe you. Decanting, for many wines, seems to only have an effect after a long time. Like a day's aeration. But then I come at the topic from the wine conservation and storage angle. At what point does aeration become oxidation?

Do we own the same Riedel blind tasting glasses?

Michael Pollard said...

Hi Marcus

Thanks for your comments.

Do we own the same Riedel blind tasting glasses? No, the glasses I’m using are neither Riedel nor the stemless O tumbler shape. My glasses are the typical ISO tasting glass in black crystal. There should be an image in this post (You may need to refresh a couple of time as the image can be reluctant to appear.) They are probably smaller in size than most would desire but I am very familiar with ISO and INAO glasses and prefer them for tasting comparisons.

At what point does aeration become oxidation? Let me answer that this way. For me the act of pulling a cork or twisting off a screwcap begins a process that is irreversible. So whether you are using François Audouze’s slow oxygenation method or splash decanting, the end effect is the same even though the length of the process may be quite different. Oxidation, aeration, or oxygenation, call it what you will, once the process starts you cannot go back. (More detail on oxidation is provided in an article by Jamie Goode, here.) The question then becomes when will it be best to drink this opened wine? I’ve certainly experienced many wines that appear to have changed in their aroma/bouquet profiles over several hours; I’m putting aside Brett or TCA influences here. However those changes have been mostly observed in a single pour of wine into a glass, and very unusually from subsequent pours of wine from a bottle. I have the impression that most changes in aroma/bouquet occur when wine is agitated in the glass. Is this due to greater oxygen uptake, the coating of the wine on a larger surface of the inside of the glass, or the warming of the wine over time that allows more volatiles to be released, or a combination of these factors – and perhaps others? The one thing I do know is that the aroma/bouquet of a wine is due to the release of volatile components in the wine – the smell, or nose of the wine.

This is why I am not a great believer in decanting wines to aerate them before drinking. I’m particularly against the type of decanting that leaves a wine in the decanter over a period of hours without any attempt to assess if exposure to the ambient environment is affecting the wine. There are a host of wine forums in which people ask how long they should decant a particular wine. In those cases where the replies are in close agreement, the period of time is usually accepted without question. And yet there is no reason to assume that the respondents have unambiguously shown that the suggested decanting does anything to the wine, or more importantly that the questioner and respondent(s) have the same ability to assess wine. In other cases the time periods given for decanting can range from a few hours to a day or more. Such information is worthless, in my opinion.

One notable exception to the above was a bottle of Australian Larrikin Shiraz that had warmed during a day of driving around Sonoma and the Russian River Valley. When opened at a restaurant, in the presence of a RRV winemaker, it was hot, unappealing and quite frankly embarrassing! Left to cool (in the bottle) for more than an hour, while we drank his wines, it became much more approachable and better than the wines we had tasted in the intervening period!


Mal said...

I have not done any specific testing (like Mike) but my feelings on decanting have long been that I cannot tell much of a difference. This is despite some friends being adamant that it does. It maybe that my palate is not sufficiently developed to appreciate any subtle or large differences.

I have heard experts say that you should decant older wines and others say that you should really decant younger wines as the exposure to the air creates an ageing process. It seems there is great difference of opinion and very little science.