Quite a good brew day today. Only one small error (heaters on Auto rather than Auto Mash, no scorching though) and I’m very very close to all my numbers, both in terms of volumes and gravity. The only exception there is the amount of trub loss when using the Trubinator, and going forward I may think about creating a dedicated equipment profile for when I’m using this piece of kit. Unfortunately doing so would effectively fork any subsequent tweaks as I’ll be tuning two profiles, so we’ll have to think about this some more.

Under-Pitched Voss

One thing which did give me slight concern today was my desperate under-pitching of Voss Kveik. If memory serves correctly I used half a sachet of slurry on a previous incarnation of Geronimo and then a quarter on Jackknife Barber, leaving me with one quarter sachet and the hope that my previous doses hadn’t been too greedy.

I warmed the alarmingly light bag during boil using my laptop, weighed it at 51.93g, and pitched it at around 24℃ with the empty bag weighing 10.71g – so 41.22g of yeast for 21 litres of 1.064. Nothing happened in the following hours and nothing continued to happen when I turned in for the night, but at around 05:00 the next day it took off in typical Kveik fashion. The following morning I was relieved to see I’d remembered to fit the spunding valve, but disappointed to find I’d adjusted it too high, because it was hissing merrily at around 17 PSI. Voss is one hard, mad bastard. Reduced pressure gradually to 5 PSI as I don’t want to suppress too many Esthers or release too much hoppy goodness via CO2 when it’s time to dry-hop. All good for now.

A good brew day without incident, the only unexpected factor being that I was supposed to be doing a SMaSH with a friend today but that was cancelled, so Geronimo it was. Not having time to make a starter and with a whole bag of OYL-061 Voss in the fridge I decided to try under-pitching and a warm ferment in order to get some of the supposedly fantastic citrus flavours creeping out.

We’ll see how that goes, but for now I’m pleased to report that despite a slow start I’m seeing strong fermentation since the small hours of this morning (approx 14 hours after pitching) and I see that the spunding valve was set way too high at 15 PSI. I’m dialling that back to 7 PSI because I want the esters to have a chance, at least until I dry-hop at which point I’ll increase back to 15 PSI to give me a safety net for cold-crashing.