Flavor contribution of flaked barley, wheat, oats & carapils

[StuckBrauer]

So I am coming up with a milk stout recipe, and I have a question.

I'm not sure what to add for body and head retention. From my understanding, flaked barley, wheat, oats, and carapils are all options. My question is what will the main flavor differences be? I've only ever brewed stout with flaked barley, so how will it be different if I branch out and use something else?

 

[dbsmith]

Expect a creamy mouthfeel from oats. I would use flaked barley instead of carapils because the haze doesn't matter in a stout and flaked barley is cheaper, though I might suspect that carapils would add a bit of residual sweetness as well which is great for a milk stout. You could also just mash higher to achieve the same result. The flaked barley is starchy. Wheat tastes like, well, wheat and will also add a nice smooth mouthfeel. For a small amount of wheat for some body, I wouldn't worry about rice hulls unless your system is really prone to stuck sparges.