Wine Words: Brett – Decoding Wine Speak And Tasting Notes

Brett is an abbreviation of Brettanomyces and a word that has been increasingly creeping into tasting notes over the years.

Brettanomyces is a spoilage yeast, almost uniquely found in reds, that introduces aromas and flavours that obscure a wine’s natural fruit and vineyard expression. At low levels, brett can bring a level of funkiness and aromatic lift that almost introduces an additional element of complexity to a wine. At higher concentrations, brett effectively scalps a wine of its fruit, leaving it dry, hard and with an impression of rusty nails.

Brett is prevalent in a lot of Bordeaux, and Burgundy, from the 1980s and before. Once established in a winery – much like a fermentation yeast that becomes ambient in a chai – brett can become a prevalent and recurring feature (fault?) in a wine year after year. Anyone familiar with the Chateaux Gruaud Larose and Talbot wines of the 1980s, even the famous Gruaud Larose 1982, will be familiar with brett from the characteristic leather and farmyard notes that became known as ‘Cordier funk’, after the family that owned these properties at the time.

The famous Chateau Montrose 1990, with a perfect 100/100 from Parker, is notorious for its brett: one bottle might be transcendental; the next, disappointingly leathery and dry.

It’s worth noting that some people really enjoy, and even seek out, a certain level of brett in their wines. There is something almost nostalgic and comforting about the sweetness and smoke-tinged coffee grounds of an older Chateau de Beaucastel or a gently funky Chateau Musar. However, few people really want the full-on sweaty saddle, bandaid / Elastoplast and uric notes of a high level brett bomb.

Chemically, the characters of a bretty wine are attributable to the molecules 4-ehtylphenol (4-EP), 4-ethylguiacol (4-EG) and a group of volatile fatty acids – which sound about as appealing in my wine as a bretty wine smells in my glass. As with most wine science, the chemistry is fiendishly complex so let’s not get more technical than necessary…

Whilst studying for my MW, and forgive the schoolboy humour:

4-EG = Everything’s Good. The most positive form of brett; the sweet leather and smoke of a seriously good bottle of mature and old school Bordeaux.

4-EP = Everything’s Poo-y. This is negative and objectionable brett – ammonia, the aggressively barnyard and, frankly, faecal.

That covers the majority if sins and, honestly, I never worried too much about the fatty acids, although I believe they are behind more rancid characters (yummy!).

So, if that is what brett is, and what it smells and tastes like, where is it coming from?

Historically, brett was a consequence of poor cellar hygiene. Once established in a winery, it was able to thrive as modern cleaning standards simply were not in place. Basically, it can live in barrels unless they are carefully steam cleaned or treated with solvents. It is a generalisation but I see Australian winemakers in particular – where brett is reviled as a flaw – as leading the charge to eradicate brett from quality wine producers. The technical proficiency and higher standards of hygiene in Australia simply forced European producers to up their game in order to keep pace.

Since the early 2000s I had really though the days of a fine wine’s vibrant fruit – be it from Pauillac, Chateauneuf-du-Pape, Montalcino or Nuits Saint Georges – being obscured behind a fog of leather and manure were behind us. However, I am once again starting to notice more and more brett in recent vintages of some very fine wines.

Brett favours an environment of high sugar, low acidity and, consequently, higher pH. White wines tend not to be infected as they are naturally higher in acid and, without the protective anti-oxidant properties of tannin, they usually receive higher doses of sulphur dioxide (SO2).

The conditions needed for brett to develop are precisely those delivered by riper, solar vintages. In other words, climate change has ushered in the potential of a new era of Brettanomyces. At the same time, the trend towards low SO2 winemaking is leaving wines without that extra level of protection against the spoilage yeast, which is why so many poorly-made natural wines are terminally brett-ridden.

That is what brett is, what is smells / tastes like, where it comes from and why it is on the rise once more. In terms of what can be done, it is much better to prevent a brett infection than to remove bretty characters – although this can be done via the use of dimethyl decarbonate or sterile filtration, both fairly significant interventions. The good news is that all you need to avoid brett in your wine is conscientious winemaking. This does not mean a clinically technical approach and nor does it mean that you have to employ high levels of SO2 if you don’t want to. There are plenty of entirely fault free and stunningly beautiful natural wines that put paid to any idea that brett is concomitant with this style of winemaking.

At the same time as climate change is promoting the incidence of bretty wine, standards of winemaking throughout the world have never been higher – which is great for those of us who prefer a wine to taste of fruit than a sweaty horse in a soiled stable!