I made a sour brown a couple of years ago, using 3763 Roeselare Lambic Blend. It remains one of the finest beers I have ever made, and amongst the best beers (commercial or homebrew) I've ever tasted.
It started life as a relatively low OG brown ale - around 1.042 - more or less in the style of Rodenbach. I threw about 20g of boiled american oak chips into the primary, to give a subtle woody flavour and provide something for the brett to live on. The Roeselare strain did a fairly quick initial ferment with the saccharomyces dominating - initial impressions after a week were that I had made a batch of English mild. Over the next 3 or so weeks, a huge pellicle formed with bubbles up to the size of a half tennis ball, and the flavour took on a lactic tang with interesting aromatics including an intriguing hint of cherry/fruit.
After about 5 weeks, I bottled half the batch - this was the plain 'sour brown ale'.
The other half of the batch was dosed with four jars of Morello cherries (black forest cake cherries), which had the juice decanted off. This caused a 2nd krausen - a pink one - followed by about a month of quite vigorous brett activity with the pellicle re-growing after being destroyed by the krausen. After about 5-6 weeks in this state, everything died down and the cherries all flocculated out to the bottom. This 2nd half - ABV% unknown - was bottled as a 'sour cherry beer'.
Both batches were superb beers, which took a good 18 months to reach their full maturity. For about the first 6 months it was fairly ordinary - unbalanced sourness, the effect being like taking a mouthful of beer followed by a sudden hit of sourness. After that it started improving and by about 14 months age was sensational. Opinion about whether the cherry or plain sour brown was better seemed to be about 50:50. A few people couldn't stand it at all.
The sourness increased a little over the first few months in the bottle, then stabilised. Every bottle formed a small pellicle which eventually dissipated. The final forms of the beers were a fairly thin & light brown ale, with refreshing sourness, a superb lactic aroma, and hints of fruit which were strangly cherry like, and a more intensely sour, reddish ale of higher alcohol with good cherry flavour and aroma, and that same clean lactic aroma.
The base recipe is attached. Note that I was playing silly buggers with over complex recipes - 4 different kinds of crystal. I'd recommend just using CaraMunich and CaraAroma. The primary should have a decent amount - say 20g - of toasted oak chips in it. Boil the oak chips before use to get rid of astringency and over the top wood flavours. If you desire a plain sour beer, allow at least a month, probably longer before bottling. If you desire a fruit beer, add the fruit at the point where you would have bottled the 'plain' beer, and be sure to bottle a few 'plain' bottles for comparision!
This is a beer I will brew again - I have two smack packs of 3763 in my fridge for that purpose.
cheers,
Colin
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