Adding more yeast to huge RIS as fermentation dies down?

[olotti]

So every year I brew a big RIS, last year OG was 1.132. Made a 3 step starter of 007, mashed at 155, and aerated for two min before pitching and two minutes at 12hrs later into fermentation. Anyway yeast eventually stalled out or just crapped out at a FG of 1.055 with ferm temps from 68-76 deg. Many processes later, like adding wlp090 starter, beta amylase etc I got the FG to 1.040. So I’m making the same stout again in a week or two, this time I made a 3 step starter with wlp090 (as it has a higher alcohol tolerance) plan on mashing at 150 deg for more fermentables, plan on aerating the same but am thinking of adding a pack of us05 as fermentation starts to die down just to make sure I chew up all the sugars. Ferm temp will be anywhere from 68-72 deg. Worth doing this or let it ride with the diff yeast I’m using and maybe the lower mash temp will add those extra fermentables not present in last years batch. Open to ideas.

 

[day_trippr]

Post your grain bill.
I invariably see folks using way too much crystal as part of a huge grain bill, it's no wonder they end up with pancake syrup...

Cheers!

 

[Dgallo]

So every year I brew a big RIS, last year OG was 1.132. Made a 3 step starter of 007, mashed at 155, and aerated for two min before pitching and two minutes at 12hrs later into fermentation. Anyway yeast eventually stalled out or just crapped out at a FG of 1.055 with ferm temps from 68-76 deg. Many processes later, like adding wlp090 starter, beta amylase etc I got the FG to 1.040. So I’m making the same stout again in a week or two, this time I made a 3 step starter with wlp090 (as it has a higher alcohol tolerance) plan on mashing at 150 deg for more fermentables, plan on aerating the same but am thinking of adding a pack of us05 as fermentation starts to die down just to make sure I chew up all the sugars. Ferm temp will be anywhere from 68-72 deg. Worth doing this or let it ride with the diff yeast I’m using and maybe the lower mash temp will add those extra fermentables not present in last years batch. Open to ideas.

As @day_trippr said, hard to give you much advice when we don’t know your bill but since it a stout with most likely 20% of the grain bill being roasted and crystal grain which have lower fermentability to begin with, mashing at 156 a 1.040-1.045 even higher is appropriate. I have a base stout that 1.108 with 12% roasted and 8 % crystal mashing at 154 I’ll finish 1.029-1.032. So I’d say you’re ball park if you’re using a typical grain bill for an RIS.

 

[olotti]

Post your grain bill.
I invariably see folks using way too much crystal as part of a huge grain bill, it's no wonder they end up with pancake syrup...

Cheers!

16lb 4oz Marris otter
1lb 8oz roasted barley
1lb 8oz choc malt
1lb midnight wheat
1lb flaked oats
1lb special b
12oz c120
4lbs dark dme in the boil at 15 min

that’s all Grain I can fit in my mash tun with 7 gal strike water so I add the dme to get the extra fermentables. I get what your saying so the MO contributes 58% of the bill plus the dme is another 14.3%. So per beersmith the mo and dme is 72% of the grain bill and the adjuncts make up the diff. Should I cut down on some of the adjuncts or does the grain bill look ok. I also always age this in secondary on bourbon soaked oak cubes for 9-12 months and last yrs batch is still on cubes but samples taste like bcbs as my goal is to go for that big thick chewy stout, that info prob would help too. If I can hit 1.040 again without all the bs I had to do is my goal if not a few FG points lower would be fine to.

 

[Unicorn_Platypus]

try using danstar nottingham dry yeast.

use 2-3 packs and hydrate. This will give you a gigantic cell count. Aerate at pitching with a large dose of pure O2. Ferment at the lower end of the temp range (60 degrees) for first fer days until fermentation slows(this will limit ester production)u. Then let that sucker naturally rise up 70 degrees (total time in primary 2 weeks from pitching, then keg/bottle).

This yeast is very neutral when fermented cool and is a beast with a 14% ABV tolerance. I've done barleywines with similar OG with no problem and 75-80% attenuation.

Cut your crystal in half. No need to use that much dark crystal. Maybe do .5# Special B & 1# of crystal 60. Replace the dark DME with light DME or Pale Ale DME. Mash between 150-153.

If you are bottle conditioning use Lallemand CBC-1 Cask and Bottle Conditioning Yeast upon bottling.

 

[olotti]

try using danstar nottingham dry yeast.

use 2-3 packs and hydrate. This will give you a gigantic cell count. Aerate at pitching with a large dose of pure O2. Ferment at the lower end of the temp range (60 degrees) for first fer days until fermentation slows(this will limit ester production)u. Then let that sucker naturally rise up 70 degrees (total time in primary 2 weeks from pitching, then keg/bottle).

This yeast is very neutral when fermented cool and is a beast with a 14% ABV tolerance. I've done barleywines with similar OG with no problem and 75-80% attenuation.

Cut your crystal in half. No need to use that much dark crystal. Maybe do .5# Special B & 1# of crystal 60. Replace the dark DME with light DME or Pale Ale DME. Mash between 150-153.

If you are bottle conditioning use Lallemand CBC-1 Cask and Bottle Conditioning Yeast upon bottling.

well I’ve already got the starter of 090 in it’s third step at this point but the nitty is something I’ll jot down for when I do this next year. What u describe as ferm temps is pretty much what I do now and I always hit it twice with my o2 wand.

I guess I didn’t think about it but yeah there’s prob more fermentables in Light dme than the dark stuff huh that may help and yeah I prob don’t need that much special b as I look at the recipe. And I’ve always used CBC 1 or Champaign yeast when bottling, works wonders. Thanks for the thougts.