Mash temperatures/schedules

[hurleyci]

So we were going to try do 2 partial mash brews tomorrow, this is our first try at using base malts so I'm unsure of how mash temperatures and schedule will change our beer. We're kind of doing boil in a bag, we'll be mashing the grains in a large nylon bag in our brew kettle.

The first beer is an imperial oatmeal stout. I've pasted in the recipe below. Most imperial stout recipes I've come across call for a single step infusion between 64 and 67 degrees. Is this just keeping it simple for simplicities sake? I'd rather do it right with 2 or 3 steps, but I know low mash temperatures will give us a more fermentable wort, so what's the point of doing a higher temperature? And which is more advisable for an imperial stout?

If low temps give less body, surely the oatmeal in our recipe will help counter this? Any advice appreciated!

Oats n Mocha Recipe:

2kg Pilsner Malt
0.6kg Oatmeal
0.5kg Chocolate Malt
0.5kg Munich Malt
0.25kg Roasted Barley
0.25kg Crystal 40L

3kg Amber Dried Malt Extract
60g Cocoa powder

30g East Kent Goldings @ 60min
20g East Kent Goldings @ 0min

Safale S-04 Irish Ale yeast

Soak coffee beans in whiskey (Jameson?) for 5 days and then add to beer after 1 week of fermentation.

Efficiency: 60% OG: 1.069 FG: 1.017 ABV: 6.8%

 

[C-Rider]

My only comment is on the addition of the coffee. Most people I think use "cold brewed" coffee (google it) and add the coffee to the bottling bucket a little at a time until they get the exact taste they want.

 

[dcp27]

you could certainly do a step mash if you want, but its generally unnecessary with something like an imperial stout. in simplest terms, lower temp means more fermentable & less body, higher temp is the opposite. personalyl i'd go somewhere in the middle of the range you said, but alot of your fermentablity is going to be controlled by the extract so its likely not to make much difference.

i'd ditch the cocoa or at least triple it. if you're only using 60g, you won't taste it