Chocolate raspberry Imperial stout

So I want to make a chocolate raspberry imperial stout, and have done a lot of research on it. Based on my reading I got my base recipe for the stout here:


Recipe Specifications
--------------------------
Boil Size: 8.24 gal
Post Boil Volume: 6.24 gal
Batch Size (fermenter): 5.00 gal
Bottling Volume: 4.25 gal
Estimated OG: 1.093 SG
Estimated Color: 52.5 SRM
Estimated IBU: 81.4 IBUs
Brewhouse Efficiency: 72.00 %
Est Mash Efficiency: 86.4 %
Boil Time: 60 Minutes

Ingredients:
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Amt Name Type # %/IBU
14 lbs Pale Malt (2 Row) US (2.0 SRM) Grain 1 75.7 %
1 lbs Chocolate Malt (350.0 SRM) Grain 2 5.4 %
1 lbs Oats, Flaked (1.0 SRM) Grain 3 5.4 %
1 lbs Roasted Barley (300.0 SRM) Grain 4 5.4 %
8.0 oz Black (Patent) Malt (500.0 SRM) Grain 5 2.7 %
8.0 oz Caramel/Crystal Malt -120L (120.0 SRM) Grain 6 2.7 %
8.0 oz Special B Malt (180.0 SRM) Grain 7 2.7 %
2.00 oz Galena [12.50 %] - Boil 60.0 min Hop 8 67.5 IBUs
1.00 oz Northern Brewer [8.50 %] - Boil 20.0 min Hop 9 13.9 IBUs
2.0 pkg Safale American (DCL/Fermentis #US-05) Yeast 10 -



I want to add chocolate and raspberry to the mix, but I don't know the best way to do it. For chocolate, chocolate bars, cocoa powder, or cocoa nibs?
Raspberry puree or fresh? And how much of each to add? I've been having a problem finding definitive answers for a starting place, I do not want the beer to be overpowering with raspberry flavor, but I do want it to be noticeable.

You've got a fair amount of chocolate malt. You may not need to add chocolate, but if you do, use a double boiler to melt your chocolate to try to get it to incorporate into the wort.

I also wonder if you have too much Special B.

I'm going to have to disagree. In big stouts, special b works great. I like to put up to a pound in my stouts. I think the recipe looks really good, very roasty though (not that that's bad).

As far as the chocolate, do NOT use chocolate bars. But to get a distinctive chocolate taste you'll need to add either cacao nibs or cocoa powder. I've never used powder, but people often add it at the end of the boil. I've used nibs a few times successfully, just adding it to secondary. 4-8oz seems to be common amount (less for a subtle taste, more for a really chocolate-y taste). If you can find some frozen raspberries, you can just toss a 2-3 pounds in the secondary.

If you do a couple searches for cocoa and raspberries, there are a lot of threads on the subjects.

Thanks for the advice. I did do searches for cocoa and raspberries, but all I could find was a lot of debating and not too much definitive answers. Which I guess is how home brewing is, but very confusing on what the best way to do things. Also, do I need to roast the nibs?

Haha, how true. Maybe this won't be definitive, but to give you another idea, I did a chocolate raspberry stout and used 2lbs of frozen raspberries in the secondary, and it had a pretty forward raspberry taste for the first 2-3 weeks of drinking (so 5-6 weeks after bottling), but faded a lot with time. At no point was it ever like fruit juice though.

This sounds really tasty. We have a high dollar grocery store here that sells a Chocolate Raspberry Chipotle coffee that rules. If your recipe turns out well, I might try it and add the chipotle.

Well just brewed it and hit 1.065 on the OG. Not so good. I batch sparge, and this is my sedond beer on this system.
I don't know if my mash temps were low. I mashed 148-154 for 60 minutes, and I added some boiling water (maybe a quart
) to increase the mash temp, when I noticed it was low.
Ended up with 9 gallons pre-boil, needed 8.24 gallons according to beer smith, so I boiled it down to 8ish gallons. Ended up with 6.5 gallons post boil, and beersmith estimated 6.24 gallons post boil.

It would be tough to hit 1.093 with 18.5lbs of grain for a 6.5 gallon batch. It takes a few brews to adjust your method to the system you have, so next time adjust batch size, or amount of grain.

Also, don't be too disappointed. Missed targets will still turn into beer. Don't mess with it, trying to bump up the abv, etc-- just go along with the original plan, but expect a delicious 6% (or so) beer!

Ok thanks for the words. I'm definitely wanting to try this recipe again after I bottle my 6% stout to try and nail the RIS style.

I'm interested to see how it turns out, looks like a great base stout to add coffee, chocolate, or fruit to.

Based on the gravity reading I decided to go 1 packet instead of 2. I should be fine right?

With that gravity, you may be on the line of whether 1 or 2 is the best. Mr Malty (a great tool: http://www.mrmalty.com/calc/calc.html) suggests about 1.5 packets for 6.5 gallon batch of a 1.065 beer. Since you already pitched, I'd say RDWHAHB.

I noticed you had also asked if you need to roast the nibs. Cacao nibs are generally roasted and dehusked beans, so roasting them isn't necessary. I don't think it would hurt, but it isn't necessary.

Fermentation has kicked off succesfully. Not to wild yet.

So how long should I leave the beer on the raspberries and cacao nibs? I was thinking 10-14 days on 3 pounds of raspberries and 6 oz. of nibs? Also thinking about soaking the nibs in a bit of vodka to extract flavors.

That sounds about right. I'd go with 14 days. The raspberries won't take long, but you'll want enough time for the nibs to impart their flavor.

I know I'm a bit late to this thread for part of the advice but hopefully not too late for the other.

I did a "Neapolitan Imperial Stout" a little while ago and it turned out great. I did raspberry, cocoa and vanilla for the "strawberry, chocolate, vanilla" of the ice cream. It's super tasty. A few things I did along the way for flavours etc.:

I added the cocoa in the mash. I did a ten gallon batch with a friend and we added an entire tin of cocoa powder (500g, a little more than a pound). Decent flavour and not at all over powering.
Vanilla was pure vanilla bean. I prepped one bean (scraped the inside of the pod and cut up the pod) and left it in a couple of oz of 12 y/o Scotch for a few weeks during primary. This was added at the end of primary for a few weeks.
The raspberries were fresh raspberries. I added them in secondary for only a week or so. I used just over a pound and it worked fine. Maybe a touch too much raspberry for my taste as I wanted it to be more of the stout flavour than the berry but it's still quite fine. If I do it again I'll use less raspberry.

So I bottled this batch on monday, and the hydrometer sample, It's a 6.6% brew, is pretty good. The raspberry flavor is good, may be a tiny bit sour, but I think that will mellow out given time. The chocolate flavor is perfect.