Am putting together a RIS and googled 'percentage of roasted malt in stouts' and this thread pops up. What do ya know, I've already posted in it several years ago. Resurrection time! :fro:
I wanted to post an update on my thinking. Obviously beer styles are continually developing and changing with taste changes in the public, both perceived and real. The more I brew the more I come to a point of formulating recipes by % of base malt. As such the RIS category 10-15 yrs ago had a fairly limited offering at even a decent bottle shop. Whereas today most commercial breweries, a number approaching 4000, are making even as a seasonal or limited release at least one Imperial Stout every 2-4 years. Thus the commercial variety and definition has been expanding.
Looking at the O.P. recipe/Jamil's recipe the roasted malt actually only accounts for 10.9, we'll call it 11% of the grain-bill. As such it's very much in line with what a lot of people say concerning various stout recipes. Even then there can be no hard and fast rules for using roasted grains in the various types of stouts.
The BYO article I'm posting a link to is a solid if not almighty voice on the subject. It does however make some keen points concerning water softness/hardness and perceived roast character. Experienced brewers know soft water is better for pale beers ergo the invention of Pilsner beer and hard water accentuates roast malts. That said one can use soft water, my general affliction, and pile on the roasted malts, the article mentions a RIS with 18% dark roasted malts creating a roasty yet softer character. Additionally the article briefly addresses varying approaches to roast character based upon style/what one is aiming toward. For example the dry roasty finish of a dry irish stout vs the soft rounded allure of a silky oatmeal stout. Based upon that article I think it would be interesting with soft/semi-soft water to hit a stout with 20% roasted barley and see what happened.
My move toward formulating recipes based solely off of %s has been hastened by my conversion to small-batch brewing (2 gallon fermenters) due to infrastructure constraints, aka tiny living quarters! My last stout was an am. stout with 9% roasted barley and 4% debittered Carafa II. At transfer after 16 days in primary it had a wonderful medium to moderate just shy of stern and far from over bearing roast character. I used bottled spring water hoping it would be harder than my tap water. Now I'm brewing a RIS to be dumped on a portion of that yeast cake. The formulation is as follows:
Avangard Munich Light: 60%
Maris Otter -----------: 17%
Roasted Barley-British: 12%
Debittered Blk-Belgian: 5%
Crystal 40 -------------: 3%
Crystal 90 -------------: 3%
So I'm looking at 17% dark roasted malt, technically 17.45% for what appears to be fairly neutral to semi-soft water. I'm actually thinking of doing a series of stouts with 10% various roasted malts in each batch, ergo 10% British Roasted Barley batch #1, 10% Chocolate batch #2, 10% Black Patent (I know!) batch #3, 10% debittered Blk batch #4. Would probably put something like 8% crystal 60 and 4% wheat, 78% Maris Otter with the same yeast:hop:water profile.
So I don't have any hard fast rules for how to build an Imperial Stout nor any other type of stout. I do however know that knowledge is great and second only to experience. In this post I attempted to share both in so far as I understand them.
https://byo.com/hops/item/2267-roasted-barley-tips-from-the-pros
