testing for 4-EP/4-EG

An interesting question has come up in the bretty regions thread in Wine Talk. To try to get some answers, I’m hoping some of you can chime in here. Do most red wines contain chemically detectable levels of 4-EP and/or 4-EG? If you do or have done testing for this, how often do you find these compounds in your wines? Secondhand knowledge of other wineries, even if you don’t care to name names, would be welcome as well. Thanks!

I wouldn’t say that it is common across all, or even most red wines. In my experience, there have been years in which almost everything had some detectable 4EP/4EG, others where almost none. 4EP/4EG is not always just from bretty wines either, I have seen a wine with no detectable brett (scorpion and plating) show up with 4EP/4EG - presumably from the oak itself. It was used as an indicator for smoke taint back in 2008, and I believe toasted oak to show the same thing…

very interesting.

Hi Doug,
I bought a California syrah a few months ago that was reviewed nationally and received a high score. I ordered it in, tasted it, and suspected it had brett due to the taste (the winery will remain nameless but DM me and I will let you know which one it was).

How many of the very high scoring syrahs have some brett in them I don’t know, ( see this article :Wine Peeps: A Wine Blog Cayuse: Unique Terroir or Flawed Wine? Lab Analysis Tells All - Wine Peeps) and as a winemaker this interests me.

So sent this suspect wine to ETS for my own edification and for $60 , got the results :

4-Ethylphenol (GC/MS) 603 ug/L
4-Ethylguaiacol (GC/MS) 36 ug/L