Qual Venti Caramel Macchiato Imperial Stout

[dlm3]

My third brew was a sweet stout with cold brewed espresso that I called "Caramel Macchiato Stout". I was very pleased with the results and got great feedback from others, even non-dark beer drinkers. Awhile back I got a bottle of Great Divide's Espresso Oaked Yeti and loved it. This got me thinking about making an imperial version of my Caramel Macchiato Stout (called Qual Venti Caramel Macchiato Imperial Stout). This will be my first attempt at a beer this big and I would like some input of what I'm thinking for the recipe and process..

The plan is to start with Northern Brewer's Imperial Stout extract kit and add the following (I'm targeting 10-11% ABV):
1# 40L Caramel/Crystal
1# 120 L Caramel/Crystal
1# Lactose (too much body for this gravity?)
1# Honey maybe???
1# Corn sugar
6 or 8 oz Cocoa Powder (3.0 SRM) Sugar 2.80% (Should I keep this or not?)
Yeast nutrient at end of boil

Secondary:
~1/2 Gallon cold brewed Starbuck’s Espresso roast (briefly boiled once grounds removed.)
3 cut & scraped Madagascar Vanilla beans soaked in Vodka ~10 days prior to secondary
2 oz Medium Plus Toast American Oak Cubes

Obviously this will be a very robust brew, but I don't want it to be too syrupy and cloying (which is why I was thinking about corn sugar to thin it a little).

For yeast I am thinking either Wyeast 1728 Scottish Ale, White Labs WLP007 Dry English Ale, or maybe Safale US-05 or Nottingham if I go with a dry yeast. If I use a liquid yeast I will likely brew Norther Brewer's Big Honkin' Stout first and harvest most of the yeast cake to pitch into this brew. Please provide any feedback about which of these (or other) yeast strains to use. I do have a digital temp controller for my fermentation fridge and I'd likely start the fermentation out at the bottom of the temp range for my chosen yeast (maybe even a degree or two cooler) to keep yeast activity in check, then maybe ramp it up a few degrees towards the end.

Aeration is also a concern as I only have an air pump/diffusion stone setup (no oxygen tank setup). I was thinking about adding the wort concentrate in two (or maybe 3) phases so that the yeast are not exposed to a super-high gravity environment. Since if I use the above ingredients I'll end up with about 3 gallons of 1.182 OG wort, if I take 1.5 gallons of this wort and dilute with 1.5 gallons of water I'll have 3 gallons of 1.091 wort. I was thinking aerate this and pitch my yeast. After two or three days, once yeast activity slows a little but is still active, I'd add the half gallon of cold brewed coffee to the remaining 1.5 gallons of wort concentrate, and add this 2 gallons to the fermenter to raise the total volume up to the intended 5 gallons, then aerate all of this for about 20 minutes. The intent being that there will be ample fermentation remaining to use all added oxygen so that staling due to oxidation won't be a problem (or that's the theory anyway). Has anyone tried this/will it work? Alternatively, I could just aerate the 2 gallons before it's added.

I'll probably give this 3 or 4 weeks in primary, and then 10 months or so in secondary.

Please provide any thoughts about any of this (recipe or process). Thank you!

 

[DragonOrta]

Don't boil coffee. That will just take the good flavors out of it and leave all the bitterness. Just use cooled boiled water and a sanitized container and you should be fine.

Coffee flavor fades quicker than most other flavors, so I would blend in the coffee to taste at bottling instead of having the coffee in secondary the entire ten months.

Since you have sugar in already, what is the honey for? It will also dry the beer out without leaving much flavor unless you doubled it up.

 

[dlm3]

I played around with cold brewing coffee when I did my first coffee stout and found that I prefer the flavor best when the cold brewed coffee was briefly boiled. Just cold brewing the coffee seemed a little too bland for me. Lightly boiling it for just a few minutes seems to give it a more robust/roasty flavor that I like, but it doesn't pick up the bitter/astringency that it would if the grounds themselves were exposed to hot/boiling water.

Thanks for the tip about adding it at bottling time though. My only concern was that adding the coffee later would water down the beer. I guess I can just compensate by not adding as much water up front, but then the OG is going to be even higher, I just want to make sure the conditions aren't so hard on the yeast that it doesn't fully ferment.

I can't say I have a whole lot of reasoning for the honey vs corn sugar, just mainly throwing out ideas. Honey seems to add extra alcohol without adding much thickness, but still contributing a nice mouth-feel. What would your recommendations be as far as how much honey and/or sugar to use?