We brewed a traditional Finnish Sahti, the “Nice Finnish” 2 days ago. I just tasted it for the first time since it’s been fermenting… It. Is. Delicious! It has a nose full of juniper and a touch of aspen on the tongue with just a bit of bite from an early hop addition. Obviously it will continue to change and develop as it ferments, but I am really looking forward to this beer!
Sahti is a traditional Finnish beer that was brewed for festive purposes, like community feasts and weddings. The Finnish have been brewing beer for over 600 years! Sahti is one of the early styles of beer that was brewed. The mash sits on a bed of wild juniper branches, which infuses the wort with differing levels of juniper depending on how long the lauter takes.
Prepping the Mash Tun with Juniper Branches
Juniper Bed of Goodness
We tried to brew our Nice Finnish Sahti as traditionally as we possibly could. This is a “field” brew, your first step is to go out and harvest the materials you will need, namely juniper branches and an aspen log. Chris and Lori took on this job with relish. The juniper really does a great job of filtering too. With a grain bill containing a bunch of chocolate rye, unmalted wheat and wheat malt, we never even came close to a stuck mash.
Juniperus Scopulorum (Rocky Mountain Juniper)
The wort is transferred from the mash tun to the brew kettle through a hollowed out aspen log, called a kuurna. Traditionally, it is not boiled at all but rather barely heated with hot stones before being cooled and fermented with Finnish baker’s yeast. The baker’s yeast Finnish brewers use for Sahti is now commercially in Finland and it produces clove and fruity accents (unfortunately, it is not available outside of Finland, unless you have a Finnish friend who can ship you some! The interwebs have not reached every single corner of the world yet). Finnish baker’s yeast is a vigorous top fermenting yeast that can reduce the plato dramatically within the first 24 hours. The recipe typically consists of dark rye and some unmalted wheat for a dark, rustic,toasty flavor.
We lined the aspen log, or the kuurna, with wild juniper twigs to impart even more juniper resin in the wort. We limited our boil to only 20 minutes (compared to the 2 hour boil we normally do!) just to sterilize the wort, and also so we could throw in a “symbolically small” bit of hops.
The Kuurna in Action
Despite my interweb savvy, we couldn’t get our hands on any Finnish baker’s yeast, and we read enough horror stories to know that American baker’s yeast would not work. So, we got creative! We mixed a couple different types of yeasts from our brewery together to replicate the clove and fruity esters found in the traditional Sahti. It has had a vigorous 2 days of fermenting, and now seems like its calming down a bit. We are so excited about this batch! We can’t wait to try it!