Sunday 8 June 2014

Brew Day: No Boil Sour

Protein RestI’ve managed to brew a lot this week, even though I’ve still been meeting with students as the school year wraps up.  Much of what I’ve brewed is intended for blending with older beers that have been in secondary for a few months, so since there was nothing special about the brew days I’ll post about them all once I decide on the blends.  The beer in this post is something like a berliner weisse, fermented with a blend of  Brett Trois and Brett C, along with a large pitch of lactobacillus.  If it turns out well, some of it will also be used for blending.

I’ve brewed quite a few berliner weisses over the last year, and the technique I use is based on the one that Kristen England outlines in Brewing with Wheat (he also talks about it a bit in this old thread from the Northern Brewer forum).  England uses a simple grist of 50% wheat malt and 50% pilsner, puts it through a step mash with a decoction, skips the boil entirely and pitches a large amount of lactobacillus along with sacchromyces at a ratio of between 3:1 and 5:1.  I’ve followed this process to the letter before, and made very good beers with it, but this time I used a variation that I’ve also had some success with: a step mash without a decoction, and a pitch of brettanomyces instead of sacchromyces.

The lactobacillus I used originally came from a pack of Wyeast Berliner Blend that I bought for cheap because it was way past its best by date.  I split the pack into two starters, one made with malt and hops to favour the yeast, and another made with apple juice to favour the lacto.  This was what I used in my first berliner, but I kept back some of the apple juice starter and I’ve been feeding it and re-pitching it successfully ever since.  I usually feed it a few weeks before I’m going to use it, and occasionally put it in the fridge if I know I won’t be using it for a while (apparently lactobacillus will eventually lower the pH enough to kill itself off, so putting it in the fridge is a way of slowing it down a bit).  I have no way of calculating a 5:1 pitch rate, so I usually just decant most of the jug (it clears after a few weeks, and you can see the wispy lacto at the bottom), and then pitch most of what’s left.

I also keep starters of brettanomyces strains in half gallon jugs, and grow these up as I need them.  In the past I’ve just used Brett Trois for these beers, but this time I decided to grow up a blend of Brett Trois and Brett C: the Trois starter was fed more recently, so I imagine it was healthier and ended up making up more of the final blend.

FermentationSome people like to give the lactobacillus a head start by holding back the yeast for a few days before pitching.  I’ve never had any trouble getting enough sourness with my technique so far, but I do worry about it, especially when the lactobacillus starter hasn’t been used for a while.  I’m hoping that the smaller size of the brett starter, along with the fact that it grows fairly slowly compared to sacch, will give the lactobacillus plenty of time to sour the beer before the yeast dries it out.  I decided to try doing this batch without any temperature control, and fermentation was pretty furious this morning.

When I’ve used this process in the past, its made sour and refreshing beers that I’ve been pretty happy with.  The brettanomyces doesn’t seem to be fazed by the acidity created by the lactobacillus, and it dries the beer right out and adds a nice fruitiness as it ages in the bottle.  (You can read comments from a competition score-sheet for one of them in this post.)  One place in which I think the brett versions I’ve made have been lacking is in the malty/wheaty flavours that were there when I used a german ale yeast and a decoction, and I think I ultimately prefer that process when I’m making a straight berliner weisse.  However I have other plans for this batch. 

Some of it will end up on fruit, probably raspberries or maybe peaches (I’ve had some success doing this before, but not with these fruits).  Assuming it gets sour enough, the rest will be used for blending with fully attenuated saisons in a few months time.  My thought its that this will be a way of adding some tartness to hoppy beers, but also a way of dosing them with brettanomyces right before they go into the bottle.  I wrote about this in an earlier post, and I’ll be trying it with some other beers soon.  It seems to be the technique that Chad Yakobson uses for making some of the beers at Crooked Stave:

“The other one is Petite Sour, which as well is going to be a full time year round beer. This beer weighs in at about 4% and the idea behind it is my version of a table beer. It’s Berliner Weisse meets Gose meets Farmhouse Wit, so it’s a tart witbier. It has an acidity level but it’s tame. It has the fruitiness from the brett (which is very characteristic of our beers as it is) but also some of the beer background as well because it’s a blend of a 100% brett beer blended with a saison farmhouse type wit which is not in oak. That beer marries all these flavors together to where it’s approachable. It’s light, crisp, clean and lemony.”

Recipe:

   
Estimated O.G. 1.033    
Measured O.G. 1.033    
Measured F.G.      
ABV.      
       
Mash:      
  133°F 60 mins  
  150°F 40 mins  
  160°F 15 mins  
  170°F 10 mins  
  No Boil    
       
Malt:      
50% Pilsner (Dingemans)    
50% Wheat Malt      
       
Hops:      
Crystal Mash Hop ? IBUs (5g @ 4.8%)
       
Yeast:      
WLP644; WLP645; lactobacillus.      

2 comments:

  1. Nice post on quick sour beers. I have a similar technique: I have a lacto/sach/brett blend that I'm continually re-pitching and once the sourness level because too much because the bacterial growth outpaces the yeast, I just add more Sach yeast.

    In addition, we also have a 55 gal drum (but this could be a keg or carboy) that we keep this quick sour blend in for longer periods of time and feed it when ever we take some out. Most places call this an acid beer and it really helps for blending.

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    1. Thanks! I haven't reused any of these blends past a few generations, but I think I might start doing this in future. I read some comments by Garret Crowell from Jester King where he said that they keep bacteria in check by pitching into hoppy beers when the population gets too high.

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