WLP004 Stalled at 1.021

[tgolanos]

I've had my Irish Red fermenting for 11 days now. I followed all my usual process in terms of ingredients, mash and fermentation (see process below), the only exception being the yeast and I added some DME because it was laying around and I wanted to get rid of it. I usually use 007 for my Reds, but I thought I'd try 004 this time. 11 days in and it seems to be stalled at 1.021.

Ingredients/Process:
3.6kg Dark Munich
0.3kg CaraRed
0.3kg CaraAroma
0.2kg Melanoidin
0.2kg Amber DME
Total: 4.6kg
Diastatic Power 33 (according to Brewers Friend)

BIAB: Mash at 65°C for 60 minutes, dunk sparge for 10ish minutes, and squeeze. Boiled for 60 minutes, allowed 24 hours for no-chill and pitched 1L 004 starter (starter fermented quite actively and healthily).

OG 1.048, prediced FG 1.011, at 81% efficiency (according to Brewers Friend).

Fermentation: 22°C (higher than normal, because Aussie summers suck) for 5 days. Very active fermentation for the whole 5 days, then it settled and kräusen dropped. Took a hydrometer reading at day 5, 1.022. I let it alone for another 5 days, sitting at around 22-24°, dependning on how well my swamp cooler works. That brings us to today, still at 1.021.

Whenever I use 007 for this beer, it's always done by day 10, reaching 1.010-1.011. If I were closer to the projected FG, I wouldn't care as much, but 1.021 is too high; I'm concerned that if I bottle it, I'll have bombs to deal with. I stirred up the yeast cake this morning and I'm going to give it until mid next week before taking another gravity reading. If it's still at 1.021, what should I do? I have a jar of 007 slurry in the fridge that I'm considering dumping in to bring the gravity down.

Edit: Added more detail after reading notes

 

[brownni5]

You might not be stalled, you might be done. With dark Munich as your base, you might not have had enough diastatic power to convert the other grains. An avg of 30 is required per pound (and I'd assume per kg), and I've seen Dark Munich listed as low as 25 - which means depending on which batch it's from, it might not even self-convert. With high-ish fermentation temps and a relatively low mash temp, your fermentation was certainly set up well. I don't think another yeast is going to bring the FG down any, but hey, you shouldn't have to worry about bombs!

 

[tgolanos]

I did have the thought that the Munich might have a lower DP than I'm used to, but this is the 5th time I've done this exact recipe. Who knows? I ran down to my LHBS over the weekend to grab things for my next brew and they recommened I try some new yeast and see what happens. I won't be able to do anything with the beer until this coming weekend, so it's worth a shot. If there's still no change, I'll assume it's safe to bottle.