RIS fermentation stuck

[FatNerdBrewing]

Hi all. I'm fairly new to homebrewing (this is my 3rd batch) and I did an extract (with specialty grains) RIS 2.5 weeks ago. Being the noob that I am I did not make a yeast starter.

My recipe was:
10 pounds dark DME
1/3 molasses
12 oz crystal malt
10 oz chocolate malt
3 oz roasted barley
3 oz black patent

and some target hops for bittering/flavor/aroma.

I used white labs English Ale Yeast and my OG was 1.091. Airlock activity stopped about a week ago. It's been in primary for 2.5 weeks and has been between 62 and 66 degrees. I took a gravity reading last night and it's right at 1.030 which certainly seemed high to me. I've moved it to a warmer part of the house last night to about 70 to see if that will do anything.

From what I've read on here it seems to me that I need to get another vial of English Ale Yeast, make a starter tonight, and pitch it into the primary when the starter is active with krausen. Does that sound right?

The beer tasted pretty good last night but if fermentation is stuck I'm assuming that means it won't carbonate when I go to bottle it.

Thank you for the help!!
:rockin:

 

[FatNerdBrewing]

Though now that I'm looking at it, 1.091 SG and 1.030 FG. That would make my attenuation 67% if I'm looking at that right which falls in the range for the yeast.

I'm not sure if that means that it's just done fermenting and it will be ready for bottling or if I need to add more yeast. Will it hurt if I add more yeast? I just would hate to bottle it only to find it didn't carbonate.

 

[MarshmallowBlue]

I used extra nutrient for my RIS and it also slowed quite a bit around the 1030 range, but mine is still going after a week.

 

[novahokie09]

English yeast strains typically have lower attenuation because they are usually higher flocculation characteristics compared to American strains, so 67% is not unexpected for an English strain.

If you do repitch, you're correct that you'd repitch at high krausen. Also, you could try re-rousing the existing yeast by swirling the fermentor and letting it sit at the elevated temperature for a few more days. If you still get the same FG reading, then you know the yeast is finished fermenting.

 

[J343MY]

Don't repitch, it's done. 1.030 is a perfectly acceptable fg for an imperial stout.

 

[FatNerdBrewing]

Don't repitch, it's done. 1.030 is a perfectly acceptable fg for an imperial stout.

Will it properly carbonate then come bottling time? I was worried if I hadn't pitched enough yeast originally that there won't be any left to eat the priming sugar. Maybe I'm not thinking of this in the correct way.

Thank you!

 

[ScottG58]

I am hoarding the last few bottles of an RIS that finished at 1.030. After tasting it, at that level, I did not want it lower. RIS IMHO needs the body to deal with the roastiness and high alcohol content.

 

[J343MY]

Will it properly carbonate then come bottling time? I was worried if I hadn't pitched enough yeast originally that there won't be any left to eat the priming sugar. Maybe I'm not thinking of this in the correct way.

Thank you!

It should have no problem carbonating properly.