Yet Another Stuck WLP007 Batch

[PerryS]

I need some help from the experts.

This is a 1.080 OG brown ale recipe from the LHBS. Claimed FG=~1.017. Seems to stall (twice, now) at 1.027. First time was last fall, cellar temp at 71F. This time at 69F.

No starter; WLP007 is simply brought to room temperature and direct-pitched from the tube into 5 gallons of 72F wort. The WLP007 takes about 12-18 hours to get going, then nearly blows the lid off the primary. I set it in a 64F closet for 8 days, and it finished at 1.027 - well short of 1.017. (The previous batch was 71F for the entire primary.) White Labs claims 70-80% attenuation, which puts FG at 1.016 ... 1.024, so I'm Not There Yet.

I stirred it up, and it lost .001 in the last four days. I'm doing the math, and it could take a while to get to 1.017, eh?



Here is the grain bill.

Extract
8 lbs Pale Malt Extract
.75 lbs Amber Malt Extract
Grain
1.5 lbs Pale Malt
1 lbs Aromatic
.5 lbs 120 L Crystal Malt
.5 lbs 80 L Crystal Malt
.25 lbs 60 L Crystal Malt
.13 lbs Roasted Barley
Mash grains for 60 minutes at 154 degrees

With these partial extract recipes, I dribble the tap water into the cooled wort, so I'm fairly certain it's oxygenated. Other recipes achieve acceptable FG. New Belgium, O'Dell, and Anhauser-Busch don't seem to have any problems with Fort Collins' water.

There are a few HBT threads that suggest Crystal Malt adds non-fermentable sugars, so maybe FG=1.017 is a tad optimistic for this LHBS recipe.

At some point, I'm willing to say the recipe is what it is, and I should just RDWHAH. But maybe I'm doing something weird to the WLP007.

 

[Lifewisher17]

Why don't you do a starter?

 

[bvn]

I teach intro brewing occasionally. Failure to adequately oxygenate the wort before pitching seems to be the commonest "mode of failure". Obviously, you are aware of the need for oxygen in the yeast's reproductive cycle. The oxygenation process I use is:
- a plastic paint paddle from Home Depot
- a Makita drill (my grandson uses a plug in drill)
- 5 minutes of whipping the wort. I have a minimal goal of 3" of thick, self supporting, foam and prefer 4" (5.5 gal of wort in 30 L Brewcraft bucket). And, yes it does splatter on occasion - clean up the splatter before it dries and gets sticky.

~4 oz of pitched yeast yields over two lbs. of cream yeast in the primary by the 7th day. The cream yeast is great for starters and baking. The leavings at the bottom of the primary are even mentioned in the Amelia Simmons 1796 cook book. Oddly, the knowledge of yeast didn't exist until about 1850 (Louis Pasteur).

 

[mooshimanx]

I need some help from the experts.

This is a 1.080 OG brown ale recipe from the LHBS. Claimed FG=~1.017. Seems to stall (twice, now) at 1.027. First time was last fall, cellar temp at 71F. This time at 69F.

No starter; WLP007 is simply brought to room temperature and direct-pitched from the tube into 5 gallons of 72F wort. The WLP007 takes about 12-18 hours to get going, then nearly blows the lid off the primary. I set it in a 64F closet for 8 days, and it finished at 1.027 - well short of 1.017. (The previous batch was 71F for the entire primary.) White Labs claims 70-80% attenuation, which puts FG at 1.016 ... 1.024, so I'm Not There Yet.

I stirred it up, and it lost .001 in the last four days. I'm doing the math, and it could take a while to get to 1.017, eh?



Here is the grain bill.

Extract
8 lbs Pale Malt Extract
.75 lbs Amber Malt Extract
Grain
1.5 lbs Pale Malt
1 lbs Aromatic
.5 lbs 120 L Crystal Malt
.5 lbs 80 L Crystal Malt
.25 lbs 60 L Crystal Malt
.13 lbs Roasted Barley
Mash grains for 60 minutes at 154 degrees

With these partial extract recipes, I dribble the tap water into the cooled wort, so I'm fairly certain it's oxygenated. Other recipes achieve acceptable FG. New Belgium, O'Dell, and Anhauser-Busch don't seem to have any problems with Fort Collins' water.

There are a few HBT threads that suggest Crystal Malt adds non-fermentable sugars, so maybe FG=1.017 is a tad optimistic for this LHBS recipe.

At some point, I'm willing to say the recipe is what it is, and I should just RDWHAH. But maybe I'm doing something weird to the WLP007.

One vial of WLP007 into a 1.080 wort is a pretty dramatic underpitch to the tune that you're only pitching 1/3 of the yeast you need. Mr. Malty's calculator suggests you should be using three vials if you're not doing a starter. For me personally, a 1.080 wort for me is a 2L starter, decant and then step up with another 2L. If you don't want to do starters, I strongly suggest you switch to using dry yeast; WLP007 and S-04 are very similar (if not the same) yeasts.

 

[aiptasia]

Agreed. Underpitched if you only used one vial. Adding O2 and yeast nutes will also help.

 

[AmandaK]

Those poor yeasties! Super under-pitch on both accounts.

I have never had a problem with WLP007 finishing correctly. In fact, sometimes it goes a bit too low.

 

[PerryS]

Thanks, guys. I'll try the starter and aggressive O2 next time.

The White Labs label on the vial says it's good for 5 gallons. I now see at the end of the fine print a suggestion for a starter when SG > 1.070.

... and thanks for the Mr. Malty pointer.

 

[hairy]

For OGs higher than 65, I always do a starter even from a fresh vial. The only exception is when I just harvested the yeast from a previous batch.

Underpitching seems to be the issue at hand though under aeration could make it worse.

For now, perhaps you can pitch another vial of yeast. To be completely safe, do up a well aerated starter and pitch the yeast at high krausen. If krausening still fails to bring the gravity down after a week or 2, I'd say bottle them but half the priming rate. I have exploding bottles before and I must say it ain't pretty. I rather undercarbonate than explode.