Two days ago the krausen started to subside, opening up several holes in the surface with fermentation slowing right down as tracked by Tilt. We’re still ostensibly short of target and I’m used to seeing the yeast disappear completely at this point, but it’s still hanging around at the edge of the vessel and there are still some meatballs floating around which haven’t (and probably won’t) broken down to smooth waste. Not sure wether to add some fresh yeast for a secondary fermentation, but as I’ve been at 8 PSI now for about a week it’s not going to make any racking or re-pitching too much fun. Maybe just cold-crash and keg, hope for the best.
There was some doubt at the back of my mind as to whether or not half an 18 month out-of-date sachet of Kveik would be viable, but this morning around 08:00 there was enough Krausen to cover almost 50% of the brew’s surface. An hour later the cover was complete, we’re up to 8 PSI on the spunding valve, and all vital signs are good. Go do your thing, you mad Norwegian bastard.
Pretty good brew day today, must be my second or third run with the new manifold? I wasn’t anticipating any problems but wanted to throw in some rice hulls all the same, this being my first ‘light’ beer seemed like an ideal opportunity to try and get by without stirring. Might have been a tad too much (or not?) but regardless, the mash went well and I was looking at over 90% efficiency. No issues today, solid brew.
I believe I was right to attribute yesterday’s initial bubbling of the blow-tube to temperature expansion since there was no sign of foam, but this morning’s a different story, with a nice cake of healthy krausen sitting on the FV’s surface just 18 hours after pitching.
Geronimo II performing into the blow-off tube
The blow-off tube is popping constantly and the spunding valve has settled on exactly 5 PSI and is hissing quietly. I’m wondering if 5 PSI is enough to suppress some of the yeast’s desired character so maybe we’ll try one without pressure at some point, but for now I like the head start on carbonisation and prevention of O2 ingress during cold-crashing.
It’s 21:15, about eight or nine hours since pitching, and this Kveik has just taken off in the last hour or so. I’m seeing a growing carpet of foam on top of the wort and have fitted a blow-off bottle, moving the spunding valve away from the likely erupting Krausen.
I’ve set the spunding valve to 10 PSI by dialling it high and filling the blow-off bottle from my CO2 tank, then reconnecting the valve and opening it until the pressure dropped back down to 10. Unfortunately I didn’t de-pressurise the bottle further, and when I reconnected it to the FV a small amount of sanitiser rushed up the dip tube as the vessels equalised. Hopefully that won’t trouble the wort or the yeast too much in this important early stage – oops!!
