Monday, November 26, 2012


This weekend I brewed a new beer using a new technique. Ever since going to Belgium a couple years ago and being introduced to non-fruity lambics, I have been a big fan of the style. When I first returned home, I wasn't able to find any gueuze in the local market, but thankfully with the recent uptick of interest in sour beers, they have started to show up at local stores. I really enjoy the sourness and the complexity of the taste of lambic beers and gueuze in particular.

So what is a lambic and more specifically what is gueuze? A lambic is traditionally a spontaneously fermented beer which is both light in color as well as light in hop bitterness/flavor. By 'spontaneously', I mean that the traditional lambic beers were given the opportunity to ferment from the natural yeasts that the beer pulled in from the air immediately after the boil. Traditional brewers will finish the boil and then move the wort into an open-air pool in which it will slowly cool (traditional methods require brewing in the cooler months of the year in order to chill the wort with the cold open air) and absorb both natural yeasts and bacterias. Then the beer is moved into a stainless vessel for the primary fermentation until it is finally transferred into a wooden barrel where it will live typically 1-3 years and continue a long, slow fermentation process. That beer is a lambic beer. To make gueuze, a brewery will  blend different age lambics to produce a special blend that is bottle-aged further before distribution.

I keep using the adjective "traditional" because most brewers are using a different, more controlled process these days. Brewers have figured out what natural yeasts and bacterias create the desired flavors and now brew lambic beers in much more controlled environments. Cantillon, one of the last (maybe the last) traditional lambic breweries still uses the open methods, which is interesting since the brewery is in a relatively dirty and industrial part of Brussels. Using traditional methods, brewers are less concerned about keeping a closed system and keeping their beer from being contaminated because the wildness and bacteria that enters their beer is what makes the beer exceptional. On the other hand, the people at Cantillon also admitted that they lose about 30% of their beer due to wildness that didn't quite work out, creating off flavors that were beyond repair. (By "repair, I mean that Cantillon often uses their less tasty lambics for their fruit beers since the fruit will help mask the off flavors.)

So anyway. I like lambic beers, but they are expensive because of the effort required to brew them. So I figure I may as well brew my own. The recipe for a lambic is quite simple, really: just some pilsner malt and some unmalted wheat. The mash process is what takes much more effort. As I mentioned, a lambic requires much more time to develop in the fermenter than a normal beer, a year typically being the minimum. What this also means is that the yeast and bacterias will need something to eat on over the course of that time period. That is one of the main reasons for the unmalted wheat. By not fully converting the starches to sugars in the usual way, not all of the sugars will end up fermentable and so can be "processed" (by yeast and bacterias) in other ways. There is a lot more science to it that I don't understand, but that's the gist of it as I do understand it. So what that meant for me on brew day was a different mashing process than my normal routine. Typically I just add all of my crushed malt to hot water so that when mixed my mash will end up in the neighborhood of 150 degrees F, and then I just let it rest for an hour for the starch conversion to take place. For this beer, I did what is called a step infusion mash. This is one where I dough-in at a lower temperature and slowly bring the heat up in stages by either adding hot water or removing and heating up some of the mash water at different stages. It ended up taking twice as long to mash, but I ended up in the neighborhood of my target gravity, so maybe it all worked out? Step infusion mashing is a new thing for me, and there are quite a few different techniques out there to achieve similar results, so this is a learning process and I will likely use a different technique next time. It also should be noted that reaching my target gravity is not a guarantee of success since my goal was more complexity in the end product. Only time will tell.

The rest of the brewday process was mostly typical. I did run off a larger volume of wort to allow for a longer boil than usual. Also, I used aged hops in the boil which are primarily used for their preservative effect and not their bittering effect.

Regarding the yeast, I struggled with the approach to take. I was really interested in trying to do truly spontaneous fermentation by putting my wort out on the back porch to allow it to collect natural yeasts and bacterias like they do in Belgium. The Cantillon brewery used to be near orchards and other natural surroundings that provided the natural yeasts to create their beer, but now it appears to be surrounded by city and industry; not exactly the picture of a natural world providing an abundance of yeast and good bacterias. So originally my thinking was that if they can collect the needed yeasts in the middle of the city, then certainly I can in my back yard (which is a wooded valley of sorts). The more I thought about it and read information from Cantillon, though, the more I decided that even though their surroundings may not be ideal, their attic space where they have chilled their wort for decades (centuries?) has a natural history that I don't have. That attic room is like a sanctuary to yeast and bacteria and has a life of it's own. The magic isn't in the air blowing into the windows as much as the wood and dust and history of that room and the brewery in general. That is something I don't have. So in the end, I ended up using some neutral yeast (which had an IPA as a "starter") to do the primary fermentation and when I put the beer in the secondary, I will add in a mixture of magic additives sourced, grown, and standardized from the likes of Cantillon, similar to how the non-traditional lambic breweries make their beer.

So the process has started. I do want to end up making gueuze, so I will likely brew another batch or two this year so that I have some for gueuze and some I can drink as a single vintage lambic. This feels like a whole new world of brewing beer, which I am excited for, but not overly excited since it will be at least a year before I can do anything with this beer, and that's if it ends up ok. At any rate, I need to figure out where to store all of these fermenters.