A fairly good brew day today with no major mishaps. I’ve tweaked the recipe slightly in order to get the most out of my 35 litres maximum mash volume, ending up with 33.4 litres and aiming for batch size of 17 litres at 1.081 OG and 8.9% at the end.
In hindsight I could probably have squeezed another half a percent ABV out of my remaining 1.6 litres play room, but that would have made things even trickier.
As it as my dough-in felt like it took twice the normal amount of time and I didn’t think I was going to get everything wet for mash rest. Once underway the flow was quite good with 250g of rice hulls to help things along, no threat of stirring needed and I finished with a mash efficiency of 65% – nowhere near the 75% indicated by the recipe (How? Why?) but perfectly in line with expectations of my equipment profile – for the first time on Yeti.
I’m writing this almost 24 hours after pitching 3 packets of M44 dry (smashed the flask on Sunday) and although sporadic bubbles were heard while cleaning up the kettle yesterday, it’s still not anywhere near as ferocious as WLP-002 was with Blair III two weeks ago. Will be interesting to overlay the fermentation curve over the previous Yeti when we’re done.
Brew Day Notes
0720 Mash rest. Dough in took quite a bit longer than normal and there’s a lot in there today. Some stoping about on top needed in order to get everything wet for mash rest. Mash temperature tricky too, with some parts registering 66℃ and some 62℃. Looks like about 34.8 litres in there.
0810 Start mash after first stir. It’s fluffy enough and thoroughly submerged at 34 litres indicated. Core around 65℃ and flowing well is slowly.
0845 Satisfactory mash so far; about an inch spare until malt pipe maximum, with roughly 4 inches of height difference between that and the kettle. Levels holding steady with no need for stirring so maybe 250g rice hulls was the sweet spot for this grain bill. Core temperature 65.3℃ with tank at target of 67℃, heaters idling at 20% in Mash PID. Pump is at 25% and centre / re-circulation ratio about 50:50.
0920 Continuing to mash while trying to bring core temperature to 75℃ for mash-out. Taking quite a while even with heaters at 100% manual. Been at it for about 10 minutes and while foam is starting to build above the elements (still circulating) the mash core is just at 70℃. I don’t want the top getting too hot so I’ll stop soon. SG 1.067 (1.045 @ 70℃) and levels approx 33 litres before sparge.
0930 Lifting malt pipe, lazy sparge with 1 litre of water from saucepan @ 77℃, can’t be bothered with HLT for such a small amount and want to keep the pump moving. Pre-boil SG 1.068 (1.050 @ 63℃) against expected 1.072. Bizarre. Why higher than before sparge? Levels 21 litres, expected 22.6 and now tracking for 8.6% ABV if boil-off is on track. I predict not.
1100 Cutting in chiller and Trubinator. Levels before 19 litres (expected post-boil volume 20.21) and 1.080 (SG 1.049 @ 80.3℃) against expected 1.081, so not too shabby there. Tracking 8.4% ABV, not doing any top-up after FV transfer.
1130 Boil over, start chill.
1150 Transfer started. Pump feels like it’s struggling a bit but stable at 27% with return temp at 21℃. OG 1.080 (1.076 @ 33.3℃) with 16 litres in the FV.
1245 Clean-up finished, 3 packs M44 pitched dry, red Tilt deployed.