Not reaching final gravity

[Job_Beer]

I have a homebrew that's been in the FV for nearly three weeks, but it has not dropped to the FG I was expecting... I've not had this problem before, so am a bit worried about what would happen if I bottle this at a higher gravity than I was expecting. Am I likely to get exploding bottles?

The beer's probably been fermenting at a slightly lower temperature than ideal for the yeast I've been using, so I'm planning on leaving it a little longer to make sure I have actually reached my FG.

I was also thinking back to the brew day itself. My mash was a bit hotter than I would have liked it to have been and I think I've read that this might have affected things. The OG was about right for what I was expecting though. Could this still affect the FG?

Any thoughts or advice would be much appreciated!

 

[steve denholm]

I've just done a AG dunklewiesen with the same problem came out at 1.020, I warmed it up stirred up the yeast added hops nothing changed it, so i bottled it and it's now mostly drunk :)

 

[Sandimas]

It would help if you told us your OG, FG and what yeast you are using - it could be slow, it could be a stuck brew, or it could be OK and your expectations or instructions were just too ambitious.

 

[Job_Beer]

Thanks guys.

My notes are at home with the exact numbers, but I got around 1.038 as OG and it looks to have bottomed out at 1.020. I'm using Wyeast Whitbread Ale - 1099. Plugging my recipe into brewersfriend, the expected FG was 1.010.

https://www.brewersfriend.com/yeasts/wyeast-whitbread-ale-1099/

 

[Zephyr259]

Yeah, something's not right with those numbers, what was your mash temp and grain bill?

I used that yeast a few times and it's pretty nice. I do wonder if it doesn't like low temps though as when I went over the threes brews I calculated apparent attenuation and adjusted it for mash temp I found that the first beer I made with it (a brown ale) had drastically lower attenuation than the bitter and barleywine, it was in the 60s compared to mid 70s. The brown ale was made before i had my fridge so it just fermented at whatever my house was sitting at which was probably around 16c, it seemed to be stuggling so got put next to the fire/radiators and wrapped in a blanket. Having said this, the bottles never overcarbed and it tasted good so maybe it didn't stall, or I got luck. The other brews were held at 18 - 20c and went much smoother.

 

[Job_Beer]

Time ran away from me on this one, so only just had chance to catch up.

I went over my notes and think the initial mash temperature was something like 73C. I knew this was high, so left the mash tun open, and stirred until it fell to 68C or so and then left it for a while.

I wasn't using as much grain as I would normally, but didn't really adjust the quantity of water used for it either. At the end of the mash, the whole thing had bedded down and it was difficult to sparge through, so had to stir the thing up to get it going properly.

And I ended up with a (slightly) lower OG than expected (but still a higher FG).

I never really appreciated the need for the mash temperature to be so well controlled.

In the end, I decided I needed to get on and bottle/mini keg the beer. It's going to be as weak as Theresa May, but hopefully taste okay. I've left a bit more room in the bottles/kegs as insurance against bottle bombs.

At least I've learnt something and got an excuse to have another go at the same brew again to see the difference doing it properly will make to the beer.

 

[Sandimas]

The high mash temp does sound like your problem. I've only ever gone as high as 68C, was going to try 70C new time as I want a sweeter brew but 73 sounds a bit too high.

I normally start with a strike temp of 73C or so, then when I add the grain it drops to around 65C. Not sure how many AGs you've done but you'll get familiar with your kit and processes after a few, and be able to get more predicable results.

 

[Job_Beer]

I've done a few brews now and been successful with them - this is looking like it will be the first one I've messed up. I had a sample when I bottled it and it didn't taste too bad, so am hoping it will be drinkable at least.

Do you think I'm at risk of having bottle bombs? Or are the unfermentables that have led to the high FG just going to stay in the beer?