Comment on Stuck fermentation?
SpiderShoeCult@sopuli.xyz 6 months ago
What is your brewing setup? I’ve used your grain quantities in BeerSmith with a Braumeister 20L setup for the out of the box efficiency (without stirring the malt during mashing or a finer grind or extra boiling) and it gave me a post-boil of 1.042, which seems to fit with your result so I’d guess you had an efficiency issue. How did the mashing go?
I’ve noticed that when boiling for the standard 1 hour, I get about a 10% increase in gravity (for the digits after the 1 - that is, pre-boil of 1.064 leads to post-boil of 1.070 ish), so in your case 1.037 to 1.041 would check out for me.
For my brewing setup, 30 minutes at 63C doesn’t really cut it, I’ve tried it and noticed 60 minutes or even 90 minutes work way better. But then I mostly use kveik and the indication seems to be for longer mash times (something about it being unable to digest sugars made of 3+ units).
I’m not sure I get your last point. If your FG is higher than expected, you should reasonably have more sugars left over from fermentation, so more residual sweetness.
Regardless, I’d suggest RDWHAHB, and see what you get out of this. Do share your final results, I am curious what it’s like.
Out of lazyness, I just let all my beers sit in the fermenter for 2 weeks and that seems to work out just fine. Some finish bubbling after 2 days, some after 12.
Aarkon@feddit.de 6 months ago
I’ve got a BrewZilla Gen 4 35L. I don’t know what you’d consider low efficiency, but the unit’s default profile in Brewfather is ~76%, whereas the software calculated roughly 65% efficiency for the batch in question. I’ve got no idea though how that compares to the Braumeister 20L other than the values in Brewfather are rather similar.
What was a first was crushing the grains myself, but mashing on itself went fine. Looking back, I might have wanted to check for starch with iodine, which I even had available. Might do next time. I also might want to add though that I used 13.5 liters of strike water and did what from my understanding is a batch sparge (raising & draining the mash tun, then adding hot water from a second vessel with a jug) with another 15 liters at 80° C. Not perfect for efficiency, I know, but as described my pre-boil gravity was fine. I must just have been to shy on the heat while boiling.
In the back of my head, I have the number of 10% boiloff being desirable, which would match with your 1 hour boil observation.
My last point is that I’m afraid the beer might be too thin as in too much liquid for too few sugars dissolved in it. I didn’t boil off enough water, so I did not concentrate the wort far enough to reach the desired post boil gravity.
SpiderShoeCult@sopuli.xyz 6 months ago
The software calculated efficiency for the Braumeister is spot on for me if just using it like set it and forget it, so about 65%. I can up that with stopping the pump during mashing, opening the thing and stirring the mash about once every 30 minutes in my 90 min mash. Also by milling the malt a bit finer. But too fine, and I get a stuck mash. With this, I managed around 75, or how much the software sets as standard for pot and cooler method, so I’m happy with that.
I also start the brew with 23ish liters of strike water, dump 6 kg of malt in there and sparge with 5-6 liters at 80C. Boil 1 hr and end up with 18-19 liters in the fermenter with the rest full of trub in the Braumeister (2-3 liters maybe?) I never measured how much is left and I can sparge with 4 or 6L. I just eyeball it according to how much wort is in when I lift the malt pipe.
In your case, I’d say maybe the mash did not go very well.
I wouldn’t be too worried about the body. It could be that your fermentation just stopped a bit higher because all that’s left is longer sugars, unfermentable, but good for the body. One way to find out…