Same same! Yesterday was brew day for a Guinness-dark sahti x stout. It was my first beer recipe and this run is the fifth time making it.
Traditional sahti is very well available in my area (not the case for all of Finland) so my stuff can be a bit less trad: 1300 EBC black malt and some Simpsons caramalt backed with a hint of rye malt and standard issue Viking sahti-malt. A particular fresh yeast is the only required ingredient according to EU authentic produce guidelines, that’s what’s bubbling mine. Cheers & merry Xmas!
Impressive research there!
I also did some googling. The production of this particular yeast was sold off to Canadian company Lallemand in 2007. It is still made at the Polttimo facility in Lahti, Finland, where Viking Malt products are also made. And this is the actual product. I use half a pack (25 g) for 21 L of beverage.
There are Sahti brewing competitions locally and an annual Finnish championship too. To participate, one does not need to employ the traditional mashing procedure. I understand the yeast has got to be that particular stuff though. It gives the brew a banana-like sweetness.