Imperial Milk Stout Recipe - Opinions?

[lupulinlibations]

Hey everyone.

I've been reading all the useful info here for a little while now, but this is my first post.

I just recently purchased another secondary fermenter and decided I want to do a really big beer that requires some more conditioning time. I used Beer Alchemy to help me put together a recipe for an Imperial Milk Stout. I've been an "extract with steeping grains" brewer up to this point. However, I'm moving up to partial mash for this beer. Here's what I've got.

Grain for partial mash:
2 lb of 2-row malt
0.5 lb of Black Malt
0.5 lb of Chocolate Malt
0.5 lb of Roasted Barley
0.5 lb of Flaked Oats

Extracts and sugars for boil:
6 lb of Pilsen LME for 60 minutes
3 lb of Pilsen DME for 60 minutes
1 lb of lactose for 10 minutes
1 lb of corn sugar for end of boil

Hops:
2 oz of Warrior for 60 minutes
1 oz of Nugget for 30 minutes
1 oz of Nugget for 15 minutes

Yeast:
Wyeast 1028 London Ale

Beer Alchemy is predicting 1.095 OG, 1.023 FG, 78 IBU, 40 SRM, and 9.7% ABV. Based upon what friends with partial mash experience have told me, I used 55% for the mash efficiency.

What do you think?

One of the main questions I have is this: How much time should I leave it in the secondary?

Thanks in advance for any input.

 

[smagee]

That efficiency number seems awfully low for such a simple grain bill; I typically use 70%, or 65ish if I have a lot of specialty grains. I don't see any reason yours should drop that low unless you're planning on mashing for 15 minutes at 158F or something .

Since the bill on this is relatively simple (at least by RIS standards), you'll probably be in good shape with between 1-2 months in secondary. I'd still give it longer to condition in the bottle/keg, but overall I think it'd be drinking fine in 3-6 months, grain to glass. Were I brewing it, I'd probably go 1 month primary, 1-2 month secondary, 1.5-2 month bottle/keg.

 

[Jakemo]

Any particular reason you want to use corn sugar in the boil? I know it raises the alcohol content, but... why?

 

[lupulinlibations]

That efficiency number seems awfully low for such a simple grain bill; I typically use 70%, or 65ish if I have a lot of specialty grains. I don't see any reason yours should drop that low unless you're planning on mashing for 15 minutes at 158F or something .

Since the bill on this is relatively simple (at least by RIS standards), you'll probably be in good shape with between 1-2 months in secondary. I'd still give it longer to condition in the bottle/keg, but overall I think it'd be drinking fine in 3-6 months, grain to glass. Were I brewing it, I'd probably go 1 month primary, 1-2 month secondary, 1.5-2 month bottle/keg.

Thanks for the info! Yeah, I thought the efficiency number seemed low, too. I just tried to make an estimate based off friends' experiences. Since this is my first partial mash, do you have any suggestions that might help? I was going to aim for 1 quart of water per pound of grain for an infusion mash in a cooler for 1 hour at 154F. I also planned to do 1 quart per pound for sparging, but I haven't decided on the temp for that yet.

I had around 2 months secondary time mapped out in my head, but I hadn't thought to leave it in the primary for a month. At this point in my homebrewing experiences, the longest I've left a beer in the primary was 17 days. Will I get any off-flavors from extended time in the primary? I'm more than willing to try it, just curious because I've never done it.

Any particular reason you want to use corn sugar in the boil? I know it raises the alcohol content, but... why?

I guess I was aiming for the beer to be near 10% ABV when finished, but didn't want to add too much more to the FG. I also wanted to maybe add just a touch of dryness to this big brew. Corn sugar seemed like the way to go to help with both of those things. Maybe I'll just leave it out, but I haven't decided yet.

 

[smagee]

I was going to aim for 1 quart of water per pound of grain for an infusion mash in a cooler for 1 hour at 154F. I also planned to do 1 quart per pound for sparging, but I haven't decided on the temp for that yet.

That seems reasonable; I usually just let Beersmith tell me how much water I'm using and leave it at that, so I'm hardly an expert at the actual calculations . 154F is a little higher than I'd go, especially if you're concerned about efficiency. I'd shoot for somewhere around 151-152F, which should give you good conversion while still leaving some residual unconvertables (which you'll be wanting in an RIS).

Keep in mind that the extracts will carry a certain percentage of non-fermentable sugars in them as well, so I'd do a PM RIS lower than an AG version, hence my suggestion above. For AG, 153-154F would be a bit more reasonable, but in this case I'd err on the side of lower temps to balance the extracts.

Will I get any off-flavors from extended time in the primary? I'm more than willing to try it, just curious because I've never done it.

This issue is a bit of a hornet's nest in the forums, but I think even the "always use a secondary" crowd would agree that leaving it on the cake for a month won't result in any off flavors. I typically leave *all* my batches on for 28 days, unless I'm doing a really light/fast beer. I find it helps with a number of things, such as ensuring that fermentation has actually finished, letting the krausen drop out of solution, etc. There are arguments that longer time on the cake allow the yeast to "clean up" after themselves as well. If you have some spare time someday, do a quick search on "secondary or no secondary" and prepare to lose a few hours .

I guess I was aiming for the beer to be near 10% ABV when finished, but didn't want to add too much more to the FG. I also wanted to maybe add just a touch of dryness to this big brew. Corn sugar seemed like the way to go to help with both of those things. Maybe I'll just leave it out, but I haven't decided yet.

I don't think you need to omit it from the recipe itself, but I agree with the above point in that I wouldn't add it during the boil. The corn sugar will help dry it out, which is especially nice due to the extract residuals I mentioned above, but since it's a simple sugar, the yeast could get overwhelmed by the initial gravity of the brew. For batches this size in which I'm using dextrose or sucrose, I usually add at least a portion of the sugar a few days into fermentation. In this case, you might want to give the brew 5-6 days of active fermentation, then dump the sugar (boiled and dissolved, of course) into the bucket/carboy. This will ensure that the yeast doesn't gorge itself on the simple sugars and decide to totally ignore the more complex ones provided by the grains and extracts.

Delaying a bit of sugar addition also serves the side benefit of reducing the amount of blowoff you will expect from the fermentation process. And I hope you're planning on using a blowoff tube; without fermcap or some other agent, this batch will be pumping out foam like nobody's business, so don't trust an airlock for it!

Apologies to all for the wall of text; it didn't seem this massive when I *started* typing...

 

[lupulinlibations]

smagee, thanks for all the tips and info. I really appreciate it. I'll use that knowledge to my advantage moving forward. Now I hope this recipe turns out the way I'm imagining...

 

[SauceBoss]

Im pretty stoked as my brother and I were actually talking about doing an Imperial Milk stout yesterday when doing a normal one. Let me know how you end up doing this and if there were any other things you would modify to get thins right. Thank!!