So heres something that I have yet to determine if it worked out for me.
I needed wheat. I forgot to buy any. I wasnt going for a wheat profile jsut some help with the retention and some body. I threw two slices of the best wheat bread I've ever had in the brew pot. Let them boil for about 35 minutes and then took the goop out. Sounded like a good idea at the time and who knows.......... Have any of you ever done that?
Maybe next time I'll through in some angel food cake or a ding dong......... I'm kidding.
ive seen people throw pumpernickel bread into a mash tun so its not unheard of... I think you will be ok but i doubt 2 slices of bread is going to do anything really for you... that would be probably comparable to 1-2oz of grain... if that.
For head retention and body, add a 1/2 pound of quick oats (in the hot cereal section). They are a pretty suitable substitute for wheat when you run short or the recipe does not call for a lot.
I have a tendancy of doing things that my other brew buddies flip out about. Too many to go through...... just things that they have never done or tried. They usually turn out really well.
truth be told....... I did it to see how it would turn out and if I would notice any difference from the last batch I made. (same grist} I think I'm gonna try one now. After drinking half a bottle of cabernet it sounds like a good idea.............. do raisns screw up brews?
Ive come close about half a dozen times from adding it to a couple stouts and a vanilla porter. Havent gone all the way yet though.