Brett beer as a style of its own

Meet Brettanomyces

Brettanomyces, usually shortened to Brett, is a genus of yeast. It is related to brewing yeast but behaves very differently. It works slowly, tolerates tough conditions and can ferment sugars that ordinary brewing yeast leaves behind. For most of brewing history it was a problem: a contaminant that made beer taste of barnyard and left bottles overcarbonated.

In some traditions it was always part of the character. Lambic, Flanders ales and some old English stock ales owed part of their flavour to Brett. Our guide to Brettanomyces covers the organism in depth.

Brett beer has its own category

Modern brewers began using Brett deliberately, sometimes as the only yeast, sometimes added to a beer already fermented with ordinary yeast. The BJCP style guidelines now list Brett Beer as its own category within American wild ales. The defining feature is Brett character without the deliberate sourness of lactic bacteria. Our guide to BJCP and BA style guidelines explains how these categories work.

That distinction matters. A Brett beer is a wild beer, but it is not necessarily a sour beer. Brett produces only a little acid on its own, mainly acetic acid when oxygen is around. Most Brett beers taste funky, fruity and dry rather than tart.

What Brett tastes like

Brett character changes with age and strain. Broadly:

• Young Brett beers: tropical fruit, pineapple, mango, stone fruit, citrus peel. Some strains lean fruity enough to surprise people.
• Older Brett beers: barnyard, hay, leather, horse blanket, smoke and spice. These are the classic "funky" notes.

The compounds behind the funk include 4-ethylphenol, which reads as barnyard or medicinal. Another is 4-ethylguaiacol, which reads as smoky and spicy. In balance they add depth. In excess they taste like a stable. Brett also eats dextrins, so Brett beers usually finish very dry and light in body.

Where it overlaps with sour beers

Many sour beers contain Brett alongside lactic bacteria. Lambic, gueuze and Flanders red are examples. In those beers, the bacteria provide the sourness and Brett adds the funk and dryness. A Brett beer, by contrast, keeps the bacteria out and puts Brett at the front.

A useful way to think about it: Brett gives funk, Lactobacillus and Pediococcus give sourness. Acetic acid bacteria give vinegar. A beer can have any mix of the three. Our guide to wild ale versus sour ale untangles the terms.

Famous examples and their styles

One widely known beer with Brett in the bottle is Orval, a Belgian Trappist pale ale. It is fermented with ordinary yeast, with Brett added later in the process. Fresh bottles taste hoppy and bitter. Over months the Brett builds a dry, leathery, funky character. Tasting a young and an old bottle side by side is a classic lesson in Brett.

Brett beers also come in many base styles: Brett IPA, Brett saison, Brett pale ale, Brett porter. The base style decides malt and hops. Brett adds a layer of fruit and funk on top.

Storing Brett beers in India

Brett works slowly and keeps working. Bottles with live Brett can keep fermenting and build pressure over time, especially in heat. In an Indian summer at 30 °C or more, that process speeds up. Store Brett beers in a cool, dark place, ideally a fridge or a wine cooler. Keep them upright so sediment settles.

Open them carefully over a sink, pointing away from people. If a bottle gushes when opened, it has probably fermented further than intended. The beer is usually safe to drink but may taste drier and funkier than the brewer meant.

How to taste a Brett beer

Serve at about 8 to 12 °C in a tulip or wine glass. Let it warm slowly, because Brett aromas open up with temperature. When you taste:

• Smell for fruit first: pineapple, mango, citrus.
• Then look for funk: hay, leather, barnyard.
• Notice dryness: Brett beers rarely finish sweet.
• Judge balance: funk should add interest, not dominate.

Brett character is a polarising flavour. Some people love it at first sip, others take time. Tasting with others and comparing words helps you build a vocabulary for it. Drink small pours with water alongside and never drive after a tasting.

Your first step: buy one Brett beer and one ordinary beer of the same base style, taste them side by side and write down every aroma the Brett version adds.

Common questions

Is Brett beer sour?

Not necessarily. Brettanomyces gives funk and fruit with only a little acidity. Sour beers usually get their tartness from lactic acid bacteria.

What does Brett beer taste like?

Young examples often taste of tropical fruit and pineapple. Older ones develop barnyard, hay, leather and spice notes, with a very dry finish.

How should Brett beers be stored?

Cool, dark and upright, ideally in a fridge. Live Brett keeps fermenting, so warm storage can build pressure in the bottle.