Differences in the Same Wine (16 April)

Shane Doohan writes the following:

Not sure if this is the right place to be sending a wine question.

Something that has been bugging me for the last couple of years is how I can buy several bottles of a particular wine at one shop and be very impressed with them, yet buy several bottles of the same wine at another shop and find that the all of the wines at the latter shop have some major flaw such as ethyl acetate (nail polish smell) or some form of bitterness that makes the wine undrinkable after it has been opened for a couple of hours. Is it possible that some of the major chains are not storing or transporting their wine properly?

Certainly there will be the odd bottle that is not up to scratch but when one opens three or four in a row with the same fault, one does get suspicious. This has happened to me so many times that I now will only buy one bottle from a trustworthy store, rush home to try it within a couple of days and if all is well, come back to buy a dozen (if they have tastings, I am saved the extra trip). I'm curious to know if anyone else has had this experience of huge variability of a wine
across different places of purchase.

On a related note, I have recently moved to America and found that many wines which I loved in Australia seem to have not travelled well. For instance, in the last couple of months I have bought Penfolds RWT 2001, Penfolds St Henri 2002 and Penfolds Bin 389 2004 from varied US outlets. All three of them had a bitter ftertaste (as my wife agreed) that became more pronounced over the two to four hours I had them open. I wonder if the companies that sell the more expensive Australia wines over here have tracked the wines to see how they present to the customer over here. I don't know what the flaw is that produces this bitterness, perhaps it has something to do with the temperature variability as the cargo ship crosses the equator. I would love to have some way of testing the wine to let the winemakers know what the flaw is, as when these wines are in good condition I think they rate fantastically for the price over here. Interestingly, I have had very good examples of Penfolds Koonunga Hill here.

TORB Responds:

I'm always happy to answer questions.

Unfortunately the phenomenon which you described is probably a lot more common than most people realise. First let me explain the technicalities so that the process becomes easier to understand.

I won't go into all the gory details, but basically, in most cases, EA occurs in one of two ways. Firstly as a winemaking fault. When this is the case, obviously all bottles are affected and that is not what you are describing. The second way in which EA occurs, rings true for what you are describing.

Once wine is exposed to oxygen, after losing its fresh flavour and taste, the oxidisation process starts to yield acetic acid. The acetic acid then reacts with the ethanol and EA is produced. The end result is vinegar. Once a bottle of wine is opened, this will happen to every bottle. Eventually. In the instances you are describing, it sounds like it's happening prematurely, because the wines are you have mentioned certainly should hold up for more than a few hours.

One very likely cause is random oxidisation. The vast majority of people would not spot a low level of random oxidisation when the bottle is first opened. However, given the wine has already had more exposure to air than the winemaker intended, it is already on its way to being vinegar, and that is why after a few hours of being exposed to air, it has declined so rapidly.

Estimates of the incidence of random oxidisation, by the experts, range from being minimal to it being a major issue. From my perspective, I think it is more in line of being a major issue. Many of the wines I pick up and go "this isn't quite right, or it is not as good as I expected it to be," are quite possibly suffering from low level random oxidisation. To make matters worse, no one knows what causes random oxidisation. They know the how, but they don't know the why. If poor storage and transportation are factors, it is no wonder you are having these experiences.

Poor transportation and storage is not just a problem with the chains. It can be a problem with all wine. On a number of occasions I have seen open trucks of wine with the sun beating down on the cartons. I have also seen trucks with no installation with wine in them when the temperature is over 35°C. In their favour, most of the chains have air-conditioned stores. Daily temperature fluctuations is the biggest enemy of wine, so even if they are being stored in less than ideal circumstances, as long as the temperature is reasonably constant, it's not too much of a concern, even if it is a little higher than optimal. Stores that are not air-conditioned are a bigger issue.

As far as export problems are concerned, on many of the US wine forums I have seen similar concerns raised about the condition that Australian wine is in when it reaches the US and Canada. If the wines are shipped in air-conditioned reefers, or if they are at the bottom of the boat, the transpacific shipping should not be an issue. But what happens when they hit the docks? Or even the wholesalers’ warehouses that don't have adequate temperature control.

So yes, to answer your question bad storage and transportation could be a factor in random oxidisation. If you are very sensitive to it, and by the sound of it you probably are, you will notice it far more than most people.

I agree with your comments in relation to the value of the Penfolds wines in the US. They are fantastic value, and when you consider that Bin 389 is the same price as Bin 128, it either means that you guys are getting fantastic value or we are being taken to the cleaners.
 

Variation in wine is a real nightmare. It will be interesting to see, over time, how much less there will be for those wines that are sealed under screwcaps. 

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  © Ric Einstein 2008