Sorry for another question here. My imperial stout didn't fully attenuate as hoped (predicted FG 1.034, actual FG 1.040, calculated ABV is 9.3%). It's been on the yeast for 4 weeks now. I used WLP007. I was going to add champagne yeast at bottling to ensure carbonation since I'm afraid the yeast in there might not do the job. I picked up Red Star's Pasteur Champagne at my LHBS over the weekend thinking this is what I needed. However, on reading its details now (http://valleyvintner.com/Merchant2/DataSheets/Yeast/PASTEURCHAMPAGNE.pdf), it says the strain is Saccharomyces bayanus and not cerevisiae. It also says it isn't used in sparkling wines. So I'm wondering if I got the wrong yeast. If I did, no big deal, it cost less than a buck, I'll get something else. I just don't want it to chew threw the residual sugar and overcarb.
I used Lalvin-EC-1118 champagne yeast when bottling a barleywine, and it worked great. When I was at the Homebrew store, they had the Red Star there as well. I asked them which one I should go with, and they said really either one of those would be fine at bottling. I just re-hydrated a half a packet, and added it to the bottling bucket. So I'd say you'd be safe going with the Red Star as well. I can't see it being any different.
Both the Red Star Pasteur Champagne and the EC-1118 strains are S. bayanus strains. The fact that they are not S. cerevisiae is what males them good for bottle priming big beers.
I also believe either yeast will work well, but you probably need way less that half a packet, even for a big beer. See this info from Northern Brewer: Advanced Bottle Conditioning.
