Brewing with Brett - Part 1 By: Fred Brown

The allure of Brettanomyces was one from which I could not hide.  The call from these “wild bugs” has grown louder.  I have tried many beers fermented or conditioned with Brett.  These tastings have only drawn me closer to using them at home.  How could some of the complex and distinct characteristics I taste impact the beer I brew at home?  Will I be opening a can of worms by allowing these wild things into my home?  Will they take over everything?  

I have recently opened my doors and have been using more and more “Brett” in my fermentations.  I once was fearful of this wild yeast but after much deliberation, research and drinking (lets be honest this is what its about!) I fully “embrace the funk!”

In this three part series I will break down this wild wild brett, brethren of our beloved saccharomyces cerevisiae while debunking some of the myths and calming your nerves.  I hope I can encourage you also to “embrace the funk” giving Brett a try and create some of the most complex and delicious beers you have made at home!

In the next three posts I will discuss:

  • A short history of Brettanomyces and what it is actually doing in your beer.
  • Recipe formulation and brewing
  • Fermentation

A brief history of Brett:

- The earliest account of brettanomyces was documented by N. Hjelte Claussen in 1904.  He detailed that brettanomyces was what gave the finest english stock ales its characteristic and flavor as these were developed during secondary fermentation (barrel storage).

- The list of Brettanomyces strains is quite extensive, there are nearly 20 different strains.

- However in the brewing world we are most interested in:

  • Brettanomyces Bruxellenis
  • Brettanomyces  Anomalus
  • Brettanomyces Crusterianus
  • Brettanomyces Naardensis
  • Brettanomyces Nanus

Science!

There are two very different but vital enzymes which differentiate Brett from our regular brewers yeast.

  1. a-glucosidase:
  1. This enzyme is capable of breaking down the more complex dextrins in your wort that saccharomyces cerevisiae cannot.
  2. Responsible for over attenuation.  You will see some beers finish at 1.000 or lower!
  1. b-glucosidase
  1. This enzyme can ferment sugars and compounds such as:

Lactose- milk sugar

Cellobiose- found in oak/wood

Glycosides- found in hops, fruit and spices

Unlike saccharomyces cerevisiae where the majority of flavors are formed within 36 hours, the flavor characteristics with Brett can take much longer to develop (months to years)


What flavors are we talking about? Barnyard, horse blanket, apple, floral, citrus, tropical fruit, smokey, metallic, medicinal

The flavor and aromatic character varies greatly from strain to strain.

What is responsible for these distinctive characteristics?

        4-Vinylguiacol - clove

        4-ethylguiacol - spice/clove

        4-vinylphenol - smokey

        4-ethyphenol - spicy, horse blanket

        4-vinylcatechol - Bitter, smokey

        4-ethylcatechol - medicinal, barn yard

Get all that?  There are a few words in there that I am still working on pronouncing myself.  However I feel it is all very important to understand or at least have a grasp on what is happening to your beer.  The more you know the better equipped you will be to tweak the flavors in your beer.  Next time I will discuss how to do exactly just that!  

        

Sources: “Brewing with Brettanomyces the horse the goat and the barnyard”, Chad Yakobson, 2011 NHC