{"id":615,"date":"2014-01-19T18:01:00","date_gmt":"2014-01-19T18:01:00","guid":{"rendered":"http:\/\/suigenerisbrewing.com\/index.php\/2014\/01\/19\/all-brett-porter\/"},"modified":"2017-09-15T18:35:09","modified_gmt":"2017-09-15T18:35:09","slug":"all-brett-porter","status":"publish","type":"post","link":"https:\/\/suigenerisbrewing.com\/index.php\/2014\/01\/19\/all-brett-porter\/","title":{"rendered":"All Brett Porter"},"content":{"rendered":"\n\n\n\n
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It’s a cold day to be brewing
\nin\u00a0the garage!<\/td>\n<\/tr>\n<\/tbody>\n<\/table>\n

Just a forewarning – this is going to be a long post. This weeks brew is an all-Brettanomyces Brown Porter. \u00a0As readers of my blog know, I’m interested in wild brewing – I’m also a huge porter fan. \u00a0Today’s brew is a fusion of these two loves, forming what I hope will be a fantastic brew. \u00a0I find it odd that today’s wild beers are largely based on lighter beer styles, as wild yeasts such as Brettanomyces<\/i>\u00a0have a long and close relationship with darker beers. \u00a0Indeed, in its heyday (1800’s) Porter was one of the most widely brewed styles of beer. \u00a0Aged porters (often labelled as ‘Stock’ or ‘Stale’ porter) usually had gone through a secondary ferment with Brettanomyces<\/i>\u00a0that was resident in the ageing barrels. This flavour was reputedly a cherished and desired for characteristic by many beer consumers.<\/p>\n

Todays brew is a modern twist on this old tradition – instead of secondarying with Brett<\/i>\u00a0I am instead using it as the sole yeast in the beer. \u00a0This is not as simple a task as one might expect – brewing all-Brett<\/i>\u00a0dark beers is a challenge for a range of reasons. One issue is that Brett<\/i> has a tendency to accentuate the astringent aspects of dark malts. \u00a0Meaning the normal mild astringency in porter, provided by chocolate & other dark malts, can be converted by Brett<\/i>\u00a0into an unpalatable mouth-drying astringency. \u00a0Moreover, the polyphenols found in the hulls of darker malts can act as substrates for the enzymes in Brett<\/i>\u00a0which create unpleasant mousy and plastic flavours (e.g. 4-ethyphenol). As such, careful planning of the recipe and brewing methods are required to minimize the formation of these unwanted flavours. \u00a0Lastly, bretts<\/i>\u00a0digest a lot of the dextrins that provide body, meaning we have to provide body through other mechanisms.<\/p>\n

But the use of Brett<\/i>\u00a0offers a number of interesting possibilities – most notably, the unique impact Brett <\/i>\u00a0has on flavour. \u00a0Brett<\/i>\u00a0produces a rage of unique flavours through two mechanisms. The first of these are fermentation products, both phenols and esters. While the phenols can be desired (leather & earthy flavours\/aromas) they can also be undesired (burnt plastic, mousy, old socks). The esters, however, are a unique canvass for us to work with – citrus & tropical fruits, cherries, stone fruits, etc, are all part of Bretts<\/i>\u00a0flavour\/aroma palate. In addition, Brett<\/i>\u00a0expresses\u00a0\u03b2\u2010glucosidase, an enzyme which allows Brett<\/i>\u00a0to degrade unique carbohydrates such as cellulose (wood) and some hop compounds. The later hop derivatives can also create some unique flavours\/aromas, especially those of tropical fruits like papaya & mango.<\/p>\n

Like I said, this is going to be a long post, so more details, the recipe & brewday notes are below the fold.
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Choosing a Strain:<\/b><\/p>\n

Choosing a strain of brett<\/i>\u00a0to use with a dark beer is a bit of a challenge. Phenol-intense strains need to be avoided in order to limit the production of undesired astringent and burnt-plastic off-flavours (which are an issue, given the use of polyphenol-rich dark malts). Moreover, we need to pick a strain whose ester profile works with the flavours of dark malts. \u00a0The first strain that jumps to my mind is Wyeasts Brettanomyces lambicus<\/i>\u00a0(WY5526<\/a>), which is renowned for a mild phenol profile and a wonderful cherry-pie character. Cherries work great with dark beers, and are very popular with stout brewers. Despite its near-perfect profile, there is one issue – my yeast bank is crammed full of Brettanomyces<\/i>\u00a0strains that I want to use and W5526 is not (yet!) among them. \u00a0Sadly, the White Labs brett<\/i>\u00a0strains WLP650\/653 (bank #32 & 33), DCY yeasts (#46), the DCY yeasts C1 & C3 (#67 & 68) are known to be phenolic. This leaves one all-brett<\/i>\u00a0mix in the batch – the brett<\/i>\u00a0I purified from Russian River Sanctification (#69). Luckily, it has a profile that should work – citrus (lemon peel), oak & grapes in place of cherries, but these flavour should still work well with darker malts. Likewise, a muted phenolic character that leans towards funk aromas should balance out nicely.<\/div>\n
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Formulating a Recipe:<\/b>
\nTo reduce the likelihood of producing undesired off flavours it is necessary to modify the typical porter recipe and brewing process to prevent the extraction of the undesired flavour precursors that brett<\/i>\u00a0can convert into downright nasty flavours. Mainly, we are targeting polyphenols, which are found in the husk of the grain – especially in the roast malts. My base grain bill is a classic porter bill:<\/p>\n