Wednesday, 5 August 2015

Brettanomyces and Oak Old Ale Results

Y'all wanna see somethin'?
I think this video speaks louder than words:

I have made a snot beer!

The real cause for this delicious viscosity is an infection. Originally, I wanted to just have a nice funky brettanomyces finished english strong ale. I ended up instead with two cases of buttered popcorn flavored sour snot.

The thick texture and buttered popcorn flavor are from a bacteria called "Pediococcus", which is an important bacteria in sour beer production. In normal sour beers, this phase where the beer becomes viscous is called the beer getting "sick", and is generally cleared up in a few months. In some beers, this can happen twice, or even happens in the bottle, so some lambic or sour producers keep their sour beers after being bottled to give them time in case this sickness happens again. Many famous lambic producers swear that this actually makes the beer better in the end.

The thickness is from the bacteria making "exopolysaccharides" - or long chains of carbohydrates or sugar molecules that form on the outside of the bacteria. These chains of starch-like molecules intermingle and form this matrix that give this awesome looking mess. Pediococcus also create a lot of diacetyl, which smells just like buttered popcorn or butterscotch.

The good news for sour beers that get sick is that the Brettanomyces will come along and digest these exopolysaccharides, and the diacetyl is taken up and broken down as well so that this clears up by the end of fermentation. The bad news is that this beer is already bottled, and pretty much unsalvageable.

Sources of error? Well, it could be that this carboy was right next to the "Solera top-off beer" which was being soured, but that shouldn't have contaminated it directly. It could be that I may have accidentally double dipped with a wine-theif while trying either of these beers, but I kind of doubt I would be so careless. The third and most likely cause is that I noticed some gunk in my bottling siphon shortly after bottling this beer, which may have been harboring some bacteria from a previous sour.

So, this beer is a loss. It's tragic because I've been much too busy this summer to brew much, but I will definitely rebrew this batch in the fall to reclaim it! Next time I'll remember to use some English dry hops as well.

EDIT: Actually, after chatting with some colleagues over at Milk The Funk on facebook, they all assured me that this beer wouldn't overcarbonate from the Brett digesting the exopolysaccharides. I'm going to leave these bottles and revisit them as time goes on, monitoring them for overcarbonation.

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