The wine world was shocked on October 25th when Walla Walla Valley’s Cayuse Vineyards announced that it would not be releasing many of its 2015 vintage wines due to problems associated with the cork closures. The problem described by the winery was “the presence of paraffin and an oily film in the wines.” Both of these issues were presumably the result of treatment processes used to produce the cork closures.
I have subsequently seen a number of consumers, and even some wineries, refer to the 2015 Cayuse corks as suffering from ‘cork taint.’ However, this is not the case. Although some people use the term cork taint – or simply ‘corked’ – very loosely to describe any one of a number of maladies that can affect wine, the term is used more specifically to describe wines that have a particular fault that can lead to objectionable aromas and flavors.
The principal cause of cork taint is a compound called 2,4,6-trichloroanisole (TCA), although there are others. TCA gives the wine a smell and/or taste that is often described as musty, like wet newspaper or a moldy basement. This can be quite pronounced or quite faint. Sometimes the wine may just seem muted aromatically and clipped on the palate. In addition to being caused by the cork itself, the taint can be caused by a number of other factors, such as tainted oak barrels.
Sensitivity to TCA varies dramatically. I have read that the most sensitive 5% is 200 times more sensitive than the least sensitive 5%. For this reason, when you have a corked bottle of wine, some people might smell the taint while others might not, even if they are trained professionals (I have seen this a number of times at distributor tastings).
The reported incidence of cork taint varies. In my tastings for Wine Enthusiast in 2016, over 6% of the Washington wines I sampled that used cork closures appeared to be tainted (I say appear because the wines were not sent in to a laboratory for confirmation). While I will not run numbers for 2017 until the end of the year, anecdotally at least, the percentage seems to be lower. In past years, I have found the percentage to be as low as 3%, although to me this is still a completely unacceptable percentage.
In addition to sporadic instances of cork taint, there are also occasionally systemic issues of various causes. Additionally, there can be bad lots of cork. For this reason, some wineries test each lot to try and ensure that there is no issue with TCA contamination.
So, yes, the issue with the 2015 vintage Cayuse wines was due to the cork closures, and in this case, the problem was systemic, encompassing a staggering 2,995 cases as well as 2,678 magnums. But, no, the problem was not cork taint as we typically define it.
Note: This post has been updated to fix a typo in the spelling of trichloroanisole.