Imperial Stout/RIS Estimated OG: 1.112 Estimated FG: 1.032 Estimated ABV: 10.5% Estimated IBU: 55 120 min boil 58.3% Pale 2-Row 9.7% Flaked Oat 7.8% Flaked Barley 7.8% Midnight Wheat 5.8% Chocolate 3.9% C60 3.9% Victory 1.9% C80 1.0% C120 154 mash temp, targeting 5.5 pH Bravo @ 60 Bravo @ 30 Big pitch of WY1968 London ESB fermented at 68F Vision is a thick, smooth stout with subtle roast character and a complex flavor profile of chocolate, cacao, caramel, dark stone fruit, mixed roasted nuts, and subtle roast. Hoping for the ESB strain to give those nice English stone fruit esters and leave some extra residual sweetness. Thoughts?
If you're going to use 1968 in a beer that big, I'd make sure to baby the yeast. Its rated ABV tolerance is only 9%. OTOH, with that grain bill and mash temp, I don't think you're going to get down to 1.032 anyway (more like 1.039 by my estimate, assuming a 60 minute mash), so that would reduce the ABV a bit. Also, I don't know that I would recommend a 68F fermentation temp for any RIS. I get that you're looking for esters, but I like to ferment them lower, to reduce the risk of rocket fuel.
@VikeMan Perhaps 66F then? Trying to find balance between ester production, attenuation, and fusels. Too low: I worry about underattenuation and insufficient ester production. Too high: fusels Also, perhaps I will lower mash temp to 152F.
I do not recommend mashing that high. With a big beer you will have plenty of residual sugars. I would be at 149-152. I also recommend you use a yeast with high attenuation.In my opinion Roast Barley is what makes a great RIS. Good luck!
Personally, I'd go even lower, like 64F. In the unlikely event the yeast doesn't finish, you can always bump the temp up toward the end, after you're past the fusel danger time. It never hurts to raise the temp toward the end with 1968 anyway (diacetyl cleanup). I agree that you'd probably be sacrificing some ester production. Having said that, you'd still get more esters at this lower temp than you would with something like WLP001, for example.
Honestly I’d recommend against mashing low and using a high attenuating yeast. 1.035-1.042 is the sweet spot for finishing gravity. Just did a RIS that went down from 1.115 to 1.042 using WLP002 and mashing at 154 and I’m very happy with how it’s tasting pre carbonation
+1 to 150 mash temp. With that grain bill you will have plenty of sugars let due to all the specialty malts. No experience with that yeast.
In my opinion, US05 is actually a great yeast for RIS. The neutral flavor let’s the roasty and malty flavors shine. And it attenuates pretty good, not leaving it overly sweet.
In that big of a beer 002 could be very fusely at 68. I’d stick to 64 or switch to another yeast that’s a little more forgiving at higher temps if you do want some fruit.
For what it's worth I have brewed a lot of big beers, and a few things that come to mind that are super important are yeast Choice, Mash temp, in fermentation temperatures. Regarding your yeast choice, I would choose something that is a better attenuator, in less prone to pitching esters. In a beer this big, the fermentation can get away from you temperature wise pretty quick. I recommend starting fermentation on the low end of the recommended temperature, and ramping up 3 to 5 days in to clean up diacetyl and acetaldehyde. I have used English and Irish yeast strains, and have never been happy with the results. I tend to use a 4 liter starter of wy'east 1056, and try to chill my wort to around 55 degrees before pitching. On a beer this big even 1056 can struggle to reach full attenuation, therefore you want to use a lower Mash temperature, especially with the amount of flaked adjuncts you will be using. I suspect your English ale yeast will crap out on you way before you reach your intended final gravity.
I have gotten 1968 up to 11% ABV before. however, back then I had a centrifuge and hemocyotmeter at my disposal. Spun down the starter, resuspend in PBS and do a cell count with trypan blue and pitch at 1million cells/ml/plato. Point is have enough yeast. Mash low. I also did not use crystal malts so take that into consideration with my 11% claim. Target 100 IBU at 60 min for something this big. My 2 cents. Good luck.
My only critique is why the small amount of victory? Seems too small to add much, maybe swap that out for at least some dark Munich for a bit more richness. Probably won't matter either way in a beer that big. 1968 is the house yeast of Cigar City. Good enough for Zhukov and Hunahpu, good enough for me. I've used it in big stouts with a lot of success. 66 is as high as I would go. US 05 also a great choice especially if you are planning on adding adjuncts.
