Belgian Golden Strong Slow/Stuck Ferment?

[JimL]

On Sunday, July 26th I brewed a 11g batch of a Jamil's Belgian Golden Strong with an OG of 1.075. My starter was stepped up from 1 super fresh vial of WLP570 via stirplated 2L starter cooled/decanted and added to a 4L starter and then chilled for 10 days in the refrigerator. I've heard bad things about leaving your yeast over a week in the refrigerator so I made a 1L starter and added the slurry from the decanted 4L starter the day before I brewed. Well, the yeast smoked through the small starter in ~12 hours and I left it out on the counter until 3-4 hours before pitching where I put it in the fermentation chamber sitting at 64F.

The fermentation schedule from Brewing Classic Styles called for the beer to start at 64F and ramp to 82F over the course of 7 days. I followed this exactly, keeping it at 82F after the first 7 days. 10 days into the ferment I checked the gravity and it was only at 1.032 which was really odd. The book and podcast reviewing this recipe all mentioned it should be close to done by now but there was a comment made by Jamil during the show and he mentioned if the beer gets stuck then pitch some CalAle yeast at high krauesen to finish it up unless it's at 1.020 or higher because then it probably wouldn't finish up where it's needed. Well, I figured I would give it a few more days so I carefully stirred the yeast up with a wine thief and just last night (one week later) I checked it again and it was at 1.022. Sure it's better but this beer needs to be at 1.007 to really nail the profile I'm looking for.

Both carboys are hanging out at the same gravity. I mashed the 100% continental pilsner grain bill at 149 and had 6 lbs of sugar added during the boil so it's def fermentable. I'm just thinking that my yeast took a crap on me early, possibly due to adding all that yeast slurry to the 1L starter at the end. Thoughts?

Should I get some CalAle and test out Jamil's recommendation? Maybe just say screw it and add some funk?

I'm also concerned about the pitching temp of the beer if I go with the Cal Ale option. Will I be creating recognizable off-flavors or fusel alcohols if I keep it at 82F or should I lose most of the Belgian yeast in suspension and drop it down to 68-70 for the new yeast?

[bikefoolery]

Um, I brewed Jamil's Belgian Dark Strong recipe, and it took a good 25 days to get to terminal gravity. The last 2 weeks I'd give the carboy a swirl every other day. It wasn't as fast as Jamil's ferment, but it still tastes awesome.

Otherwise bring the temp down to the 60s and work up a pitch of Cal-Ale. I would not give up on it yet. The Belgian character isn't going to disappear, most of the fermentation is already complete. The Cal Ale yeast will be doing the work, so it doesn't matter if the Belgian yeast drop out of suspension.

Have you checked the accuracy of your mash thermometer?

Good Luck.

The Fool

[JimL]

I double check my thermometer every time I brew. The digital one I use for mash temp is spot on with my old digital unit so I don't think that's it. Its a good thing to check though.

I still have some slow airlock activity and plan on pulling a reading tonight.

[TastyMcD]

I'm also concerned about the pitching temp of the beer if I go with the Cal Ale option. Will I be creating recognizable off-flavors or fusel alcohols if I keep it at 82F or should I lose most of the Belgian yeast in suspension and drop it down to 68-70 for the new yeast?

I'd drop it down to 66-68 before pitching the active starter of WLP001.

I had a similar fermet on the Golden Strong I brewed for 2007 AHA National Homebrew Competition. I was stuck at 1.028 (O.G. 1.090). I racked the beer to kegs and pitched champagne yeast (a subsequent BN Sunday Session with Shea Comfort informed me that champagne yeast wasn't necessarily the best choice so WLP001 would be better.) It fermented at 70F in the kegs down to 1.018 and stopped. I then alternated the kegs from cold storage for a week back to room temperature for a week three times and each time the ferment would kick up and stop. I don't know if it was the Belgian yeast or the champagne yeast that was active but the finished beer did have a sort of bottle conditioned flavor to it. Most of the time the beer makes itself, sometimes you have to grab the controls. It finished at 1.010 and took a Bronze medal in the second round in Denver.

Tasty

[uncle_bad_touches]

I've brewed many times with 570 and unless you get the right pitch it can tend to be sluggish. However I've never had problems with underattenuation, even with the sluggish ferments. My advice is to let it ferment out - it might take 3 or 4 weeks, but it should keep chugging away. Check your gravity every week or so and when it stops dropping then you can call it done.

[brewinhard]

My first guess would be to check your mashing (ie - was conversion complete? a 90 min rest? thermometer accurate?)
If all those are good, my second reply would be to add the majority of the sugar after fermentation begins. I have trouble getting my yeast to finish my tripels dry enough if I add all the sugar during the boil. I got way better results (w/ medals to show) by adding the sugar just as the fermentation begins to slow down. I do still add a pound of sugar to the boil, but this doesn't seem to affect how the yeast consume the maltose as much as giving them all the sugar (3#) to feed on at once PLUS the malt sugars. It seems with my experience that the yeast will quickly consume the simpler sugars (corn, cane, etc) and then get too tired or too full to finish the job all the way with the maltose like they should.
I know there are many guys on here who will say that is crazy and that they add all of their sugar to the boil, but it doesn't work in my system. Maybe something to try out for you next time if your not happy with the final gravity. BTW, if you don't get to your desired gravity and the beer tastes too sweet for your liking, I highly recommend pitching some brett and let it sit for 5-6 months. You will greatly rewarded with an amazing (and dry) beer!

[Quin]

How are you aerating your wort? Most incomplete fermentation can be attributed to insufficent aeration [paraprhase from Dan Gordon].

[JimL]

Update: I never did repitch any yeast in the beer. Over the weekend I checked the gravity on both carboys and one was down to 1.010 and the other 1.012 .

Just a few more points to go! I'll check again tonight and then Friday- if it hasn't moved they are getting kegged over the weekend. The samples are awesome but at 68F they do seem a little hot. It's not horrible but this is the first time I've brewed one of these.