What is Brett? (and why should I care?)

They're entitled to their opinions and I'm entitled to mine...

Invariably when at a wine tasting, someone will suggest that one or several of the wines is "bretty" and thereby start a cacophony of groans for the suspecting offending wine. It took me years to understand what they were talking about, as often I could not pick it up, either on the nose or on the palate. While at a tasting earlier this year, someone again suggested that a wine was "bretty" and wondered aloud if our soon-to-be release Wine Rescue would do anything about it? Well, I did know and figured that a little research would be in order. So, unfortunately, another dive into the geekiness of wine chemistry, but I promise to bring it all together at the end!

Bretty refers to a wild yeast known as Brettanocmyces that can affect wine if proper precautions are not taking to kill it off during fermentation, aging. This means making sure that sulfite levels are above 25 parts per million. For those of you who email me suggestions to keep the "chemicals" like sulfites out of wine, here is yet more evidence that you do this at your peril. This bacteria will produce a range of by-products, the family of compounds most commonly found to cause this defect are known as tetrahydropyridines. These chemicals (various isomers) cause the horsey or mousy nose and pallate when in concentrations above 1 or 2 parts per billion. Again, simplistically knowing a wine has a "Bretty" smell or taste is not quite as easy as one would think. At the tasting noted above, samples were taking to "isolate" these tetrahydropyridines. The fact is, none of them were found in either the red or the white wines suspected of being "bretty". As noted in earlier posts, this is not unusual as we all perceive things quite differently. We have found a way to isolate and spike samples of wine with these tetrahydropyrindines (for testing with Wine Rescue), and have found that our tasting panel is not always able to pick them up (well above threshold levels).