Imperial Stout Yeast Question

I see no advantage to pitching both yeasts here. The competition from S04 will mean that there is less S05 available to finish the beer. Both are pretty neutral (although I stopped using S04 because of some doughy flavors). The point is, you won't be getting great flavor from one yeast and attenuation from another, so two strains seems like more of a minus than a plus to me. If you wait to pitch S05 in secondary, it may struggle because you are pitching directly into a high alcohol environment. I recommend you use 2 or possibly more packs of S05, or perhaps use a an attenuative liquid neutral English strain like WLP007 with an appropriate sized starter. Use MrMalty.com to determine how big to pitch.

 

Maybe I should have kept my mouth shut (hands clasped?), because I do not have experience with high gravity brewing (except for meads, which we all know do not really count). I have only once pitched an ale strain in a nearly finished beer with the hope that it would finish. In this case, the beer was a lager that had a diacetyl problem. I made a starter with the ale strain, waited for that starter to get good and frothy, and then pitched when it was active. If you are pitching into secondary, I highly recommend this strategy.

I guess I think you would be better off copitching into primary here so that the S05 will be accustomed to the high alcohol. Again, I do not think you will perceive much flavor from the S04 (unless it is of the bad doughy variety), so sort of think including it is pointless, but that's my palate vs. yours, and there's no winning that argument. One thing I wonder about is flocculation. S04 is highly flocculant, the cells must clump together. I wonder if whatever cellular glue causes it to flocc could pull the S05 out too. Probably, but probably not enough to stall. Maybe have some backup S05 ready to pitch into the secondary as I described above.

Again, this is new territory for me, so I'm just spinning and speculating. Good luck. I'd be interested in hearing what you did and how it turned out.

 

Add the 04 for a week and then finish up with 05. This can all be done in primary, since you couldn't reuse the yeast anyway.

 

I've used both.. I prefer the 05 to the 04, but, I also think my process and recipe was better later, when I used 05.

If you've got a complex malt bill, and plan to age it, even in oak... I feel the yeast gets overwhelmed unless you are doing something to coax out the esters, which I wouldn't advise in a larger beer.

4 packs of 05, split in 2 carboys, and you will have good beer, if kept around 62. No need for blow off tube, and come out great.

OG was 1.125 down to 1.027 I think.

Infact.. I think I might take a pour tonight of mine, thanks to this thread.

 

Here's my favorite way of brewing a RIS, and it's my favorite style of beer to drink and brew. I get the wyeast irish ale yeast and make a moderate alcohol beer with it 2 weeks before brewing the RIS. Then, brew day, move the moderate beer to a 2ndary, and pour the chilled RIS Wort on top. Works a treat for a good strong fermentation and plenty of ability to finish it. I also use yeast nutrient for high gravity beers and strictly control the temperature.

 

I think if you want the flavor profiles from S04 you make a 9% beer. If you want a 11% beer use different yeast. Good luck!