Brettanomyces (or “Brett” if you want to sound like you know what you’re talking about) is a yeast that is found on grape skins, in barrels and in the winery itself.
Brett can be found mainly in red wines, as the color is extracted from the skins of grapes during red wine fermentation, although Brett can and does occur in white wines, and can sometimes be attributed to sloppy (unhygienic) winemaking.
Brett is actually very difficult to get rid of in a winery, so they take many steps to avoid it in the first place. Believe it or not though, low levels of Brett in wine can actually be a good thing, as it adds a touch more complexity and character (in controlled doses). For this reason, Brettanomyces is only viewed as a fault if there’s excessive levels detected.
How to tell if your wine is affected:
Brett in wine leads to a whole lot of unpleasant (but quite colorful) wine descriptors, including but not limited to; barnyard, wet dog, moldy cheese, cow pat, and sweaty saddles. On a side note, I’ve never actually sniffed a sweaty saddle, but if you have, then you’ve got more problems than just a bad bottle of wine. Seek help.
Your course of action:
Different people have different sensitivities to Brett, so you may want to get a second opinion on the wine you claim to be infested with odors of wet dog, before you do anything rash!
Click here for the rest of my —-> A Guide to Wine Faults posts.