I was looking for some yeast for a farmhouse ale, when I came across The Yeast Bay’s Farmhouse sour ale yeast (link). It’s a blend of 2 farmhouse/saison Saccharomyces cerevisiae isolates, Lactobacillus brevis, and Lactobacillus delbreuckii. This did not fit at all with what I had initially planned to brew, but sounded so interesting that I just had to buy it. It will be my first brew with lactobacillus.
First I did some research on how to use lactobacillus, and found out that they do not play well with large hop additions/high IBU. Bear-flavoured Blog was really useful, and they inspired me with their recipe that did not add any hops at all during boil / post boil. They only added hops during a short dry hop to keep bitterness down and encourage the lactobacillus to create sourness. This seemed both crazy and to make sense to me, so I decided to follow this approach. Credit where credit is due though.
Yeast Bay’s advice on using this yeast: “For The Yeast Bay Farmhouse Sour Ale, a starter is optional. If the brewers is looking for more farmhouse character from the yeast, create a normal starter with yeast nutrients, and use a stir plate. If the brewer wants to stress the yeast and favor the bacteria, do not make a starter.” I decided to pitch the yeast without a starter and some nutrients.
As for the grain bill, I wanted to keep things simple. In my research I read that adding a (really) small bit or Caramalt would be good for the lactobacillus. Unfortunately I could not find the source for this, so I can’t give credit to this source. Instead of a 90/10 pilsener/wheat, like my simple saison recipe – I replaced a tiny bit of wheat with CaraVienne.
This is the recipe that I ended up with:
Pilsener Malt (Belgian) 90,0%
Wheat Malt 7,5%
Nelson Sauvin 80g dryhop for 4 days
The idea is to leave it for about 8 weeks in the fermenter and see how the taste evolves. Once I’m happy with the amount of sourness I will generously dry hop it with Nelson Sauvin. I still have an unopened bag that has been in my fridge since October last year. I might just toss in the whole bag.
Brewing with a Braumeister and no hops made for a really easy brewday. I did a simple mash, an 80 min. saccharification stand @ 65C and boiled for 90 minutes.
After cooling down the wort I’ve added some yeast nutrient and pitched the yeast without making a starter to favour the lactobacillus.
Fermentation took off within 24 hours.
Update after 10 days fermentation
After fermentation took off I’ve slowly ramped up the temperature to 24 degrees, and kept it sitting in that temp. I got curious and took a small sip to see how the taste is evolving.
There is already quite some sourness/tart to the beer. It’s surprising to see that I do not miss the hop bitterness that much. I should have measured the pH to see how the beer is developing – which I will do on my next measure. All in all it’s developing nicely. Now I just need to sit on my hands and not touch it.
Update after 3 weeks of fermentation
Today I checked up on my beer and took a reading of the pH to see how the sourness is developing. It’s already at 3.21!
I’m happy with how this one is developing, although not completely sure where this will end up in terms of sourness. I did not expect my pH to be this low already (even though I did all I could to make the lactobacillus happy). I will take another sample in a weeks time.
Update after 5 weeks of fermentation
The pH dropped to 3.10!
High fermentation temperatures + no IBU helped the souring a lot. My plan is to wait until the end of the week and dry-hop generously with Nelson Sauvin. I’ll bottle a week later. I figure I do not need the 8 weeks as I’m happy with the acidity.
Taste notes (after 2 weeks of bottle conditioning)
Carbonation is now pretty much spot on. Head retention (like most sours) is not great, but it does pour a small head.
The taste is very fruit forward (gooseberry) – shortly followed by an acid lemon kick. The sour is not as complex as say a Geuze, but it doesn’t need to be as it works really well in tandem with the Nelson Sauvin dry hop. My girlfriend has an expensive taste for sour beers and she kept on stealing sips from my glass.
I’m really, really happy with the results. Especially after some mixed results with Brett in some previous brews I was thinking that alternate yeast/bacteria brews were not for me. It tastes like something really refined and complex, but still very drinkable. The process itself is relatively straight forward – but you do need patience. I think this might be my favourite brew so far.