Advice on high OG fermentation

So, I was gearing up to brew a tripel, which eventually became a dark strong ale instead. Everything went as planned and it’s been fermenting for 2.5 weeks. I haven’t really seen any activity since the weekend, so I took a gravity sample today.

OG = 1.115
Today = 1.047

I’m looking for thoughts on how I might expect this one to finish up. Some info:

Volume: 2.5 gal

6lb Gold LME
1lb D90 candi syrup

Steeping grains:
0.5lb Aromatic malt
0.5lb Special B
0.25lb Carapils
0.25lb Caramunich
0.25lb melanoidin
(Thank you Pietro for the recipe you posted a couple months ago)

Wyeast 3787 Trappist High Gravity

Brewtarget says FG should look something like 1.026. Is that realistic? Of course, it says the NB Barleywine recipe should finish at 1.022, and mine finished at 1.031 after primary, 1.026 after 8 months secondary/aging.

So, thoughts? While we’re at it: How long would you let this one age before bottling? The recipes I’ve compared it to suggest only a few weeks or maybe 1-2 months, but this is a bit bigger than normal.


Well, you listed details about everything except for how big of a yeast starter you made so I’m guessing there wasn’t one. One package of any yeast isn’t going to be enough to chew through that my sugar efficiently. Well, maybe just saw it was only a half batch, still that’s pushing it. I’d consult a yeast calc online if you didn’t. As to how to fix it, I’d start with warming up the beer to the higher end of the temp spectrum and trying to rouse the yeast. Anything that high in gravity I’d let age for a while. Give it a four-six months.

Just checking - you using a hydrometer or a refractometer to measure FG?

  1. Yeast starter! I used a Patersbier (OG 1.055) as the starter and ended up pitching everything that I had left after harvesting and rinsing once. Pitched the day after bottling and harvest. Turned out to be somewhere in the neighborhood of 60-90mL dense pellet (it was centrifuged). Mrmalty calls for about that range, depending on the density, so I probably overpitched a bit.

  2. Hydrometer

I pitched at about 64 degrees then moved it to my basement. The basement sits at about 60, so it cooled a bit and fermentation started about 24 hours later. Temp rose to maybe 64 for the next 5 days, then started to drop off. I moved it back upstairs on the 17th and the temp rose to 70, where it’s been ever since. I roused the yeast on Sunday, but that didn’t seem to do much. I don’t know how I’d raise the temp, except maybe point a space heater at it. Wouldn’t want to leave that running for days on end, though.

I should note that the hydro sample tasted pretty good. Not overly sweet at all, though I do like sweet, malty beer. It’s what I was aiming for, actually.

You’ve done what I would suggest (warm and rouse the yeast) and you’re using a hydrometer, so it may be done although seems like the yeast (assuming healthy with proper oxygenation) ought to have knocked off at least another 10-20 points.

Yeah, I don’t know. Warm and rouse. Extract tends to end high but that still seems really high.