Homecooked Lambic Style Brewday
Sour beer is currently trending commercially and in the homebrewing world. I will readily admit that I don’t have a lot of experience when it comes to tasting and brewing these styles. I’ve had a few of the classic examples like Rodenbach and Cantillon, but not often enough to have a strong understanding of these beers. In fact, in honor of Zwanze day (which I skipped to brew a split batch of Kolsch/Munich Helles) I tasted my first Cantillon Geuze ever. I’ll be saving some wort from my brew day to get a starter going from the dregs of this bottle (and a few others) for my next Lambic batch.
One of the main hesitations in brewing sour beers for commercial and homebrewers is the amount of time it takes to “sour” a beer. Most sour beers use a combination of saccharomyces, brettanomyces, pediococcus, and lactobacillus over the course of one to three years to achieve the correct balance of flavors. For a homebrewer living in a tiny apartment in Brooklyn, a carboy taking up real estate for one to three years in order to sour doesn’t make much sense. For this reason, I decided to start brewing sour batches at my parents’ house in rural Pennsylvania. I go home every Thanksgiving and Christmas so why not brew a lambic or other sour beer while I’m there and let it age in a relatively stable environment. The ultimate goal is to have several batches of young and old lambic to blend together into a gueuze. I also noticed that every “clean” beer I brewed there (outside at least) turned out to not be “clean”, most likely infected by the microflora wafting over from the barn across the street.
I started the tradition this Thanksgiving. Since the holidays can get kind of hectic, I decided to keep things simple and use only extract (4# wheat DME and 3# Pilsen Light DME) with a small dose (3.5 oz.) of maltodextrin to make sure the brettanomyces had some sugars to chew on for the long haul. I used ~1.5 oz. French Strisselspalt hops (2.3% AA) to get to roughly 10 IBUs (there is quite a lot to talk about concerning aged hops in lambics, but that will be the subject of a future post).
Hide your lambics away from your parents! Its fun! (photo credit: Mom)
Fermentation is the critical part of sour beers. In a traditional spontaneously fermented lambic, the microflora (saccharomyces, brett, pedio, and lacto, etc.) floating in the air drop into the cooling wort. The yeast companies sell proprietary blends of yeast and bacteria for attempting to replicate well known sour beer styles like lambic and Gueuze. Inoculating the wort with a pre-made blend of souring organisms is in no way the same as allowing spontaneous fermentation, but we’re not brewing in Belgium. I have my first sour Flanders Red going as a split batch with Ray Girard using the Wyeast 3278 Lambic Blend and the Wyeast 3763 Roeselare Ale Blend, so I wanted to try out another sour ale mix. White Labs recently released WLP665 Flemish Ale Blend which seemed like a great choice for a lambic.
Several prominent homebrewers suggest first pitching a neutral primary yeast strain and then the sour mix. With this method, the primary ale strain does the bulk of the fermentation and then the brett and bugs come in later and finish off the longer chain dextrins to give the beer that signature funk. The results are much more consistent and controllable this way, but others contend that the beer never quite gets sour or funky enough. I chose to skip the neutral primary strain and pitch just a single vial of the WLP665. Lambic producers don’t pitch a neutral strain and I wanted to follow their process as closely as possible. The beer may not be as consistent (too funky, too sour, too nasty) but that’s where the art of blending gueuze from different batches of lambic comes in.
I brewed the day after Thanksgiving this year, and when I left two days later, there was no visible fermentation activity. Pitching such a small amount of yeast (~7 billion cells in one vial) had me worried that the primary fermentation would be really ugly, but it can’t be any uglier than spontaneous fermentation. The brett should clean up any off flavors and nasty byproducts from an underpitching the yeast. Fermentation eventually took off (even in the cool 60F closet) and after bugging my Mom for days to tell me what was going on with it, she finally sent the above pic. The krausen nearly knocked the breathable silicone stopper out of the carboy! We’ll have to wait at least a year to taste the results, but I’m already looking forward to my upcoming Christmas lambic brew day.