Having
made a porter (or is it a stout?) with my diastatic brown malt I obviously wanted some
Brettanomyces character too. The problems British brewers faced when
they tried to go to single strain yeasts convinces me that Brett. must
have been ubiquitous back
in the day.
I
used B.claussenii (the mildest flavoured of the Brett. strains) for
secondary fermentation, as I’ve done successfully in the past.
Previously I’ve found two months is sufficient for it to have done its
work and the beer is then safe for
bottling.
So
that’s what I did this time round, and the beer conditioned fine and
certainly had a very interesting flavour. I was somewhat surprised when I
came back to the bottles a few months later to find that further
fermentation had been carried
out and the bottles had over conditioned. Never mind I thought, perhaps
I’d over primed, but fortunately I have a solution that problem. So the bottles
were carefully de-gassed until they were safe from fobbing. Or so I
thought.
When, after another few months I opened a bottle I was shocked to find it gushing out the top and making a mess on my kitchen worktop. Rather embarassingly it happend with a bottle I'd given away too. There was clearly more going on than I thought. With diastatic brown malt, as well as less extract I got less attenuation. Instead of the 75-80% apparent attenuation I'd normally expect it was more like 66%. I had hoped that the Brett. would help increase the attenuation to something closer to that found in a normal beer but after two months not a lot had happened which is why I bottled the beer.
As the months went by though the Brett. finally got round to it and slowly began to chomp through the dextrins that normal brewing yeast can't ferment. The increased attenuation I'd hoped for finally arrived, just a little later (and messier!) than I'd expected. Those old brewers knew what they were doing when they aged porter for a year.
As the months went by though the Brett. finally got round to it and slowly began to chomp through the dextrins that normal brewing yeast can't ferment. The increased attenuation I'd hoped for finally arrived, just a little later (and messier!) than I'd expected. Those old brewers knew what they were doing when they aged porter for a year.
Excellent - it would have sat in the big vats for a year to not only develop the tang but then de-gas so it could be shipped bottled. Now, that being said, I think I have an ad from the 1790s for a NYC Porter cellar promising the stuff was "ripe and brisk". So it's controlled not stifled.
ReplyDeleteCheers Alan, I've got more on the next thing I tried out with diastatic brown malt I'll post soon.
DeleteEverything I have read about brett suggests that you should expect a slow fermentation in secondary/bottling and a low attenuation from your first yeast will result in the brett taking a long time, perhaps a year, to get through all the fermentables. Better to be patient, I guess....
ReplyDeleteBefore I started brewing with Brett. I was expecting it to take a very long time. But in practice I've found when added to beers made with modern pale malt it has done its work in two months, at least as far as carbonation goes. Perhaps if I raised the mash temperature things would work out differently.
DeleteTrue, it all depends on how many fermentables are left over for the brett to have a go at. Perhaps the amount of brett pitched also will make a difference. Having your brett introduced by innoculated barrels is different to adding a good amount of brett by pitching. Therefore judging the time needed to be ready for bottling by looking at the time taken to condition beer in traditional barrel processes may be misleading. This is also true as the brett may be consuming the wood of the barrel once beer sugars are gone and the conditioning time may be extended to allow this process to happen, past the point where it could be packaged.
Delete