My interest in roasting grains comes mostly from wanting to try to make something like the recipe by Lcasanova here: http://www.homebrewtalk.com/f78/gluten-free-pumpkin-spice-ale-147707/
If anyone is interested in reading my post in that thread, they'll see that I'm not going to exactly duplicate the recipe. I'm using it as a starting point and trying to make something close. I'm probably going to go with hallertau hops because I've liked the results every time I've used them, but I'm going to use different grains out of necessity. I can't find sorghum locally as I thought I'd be able to, so I've roasted some quinoa and some gluten free oats.
Here's what I've done:
Quinoa: 1.5 pounds, rinsed thoroughly, started at 200*F for 15 minutes, every 15 minutes I stirred and increased by 25 degrees all the way up through 375 for 15 minutes, then removed from the oven to let cool and put in a brown paper bag. Has what appears to be a mottled color because of the structure of the quinoa. Each grain has a burnt part and part that stayed almost the same color as it started.
GF Oats: two batches, each .5 pound (8 oz) rinsed lightly, started at 300 for 30 minutes, stirred then increased to 350 for 15 minutes, stirred then increased to 400 for 15 minutes. The first 8 ounces I removed here, and the second 8 ounces I stirred and left in for another 15 minutes at 400. The lighter one turned out a nice golden sort of color and the darker one turned out much darker and is almost as brown as chocolate.
I'm thinking I'll probably try the quinoa in the pumpkin spice ale recipe and mess around with the oats in four separate one gallon batches, maybe trying to burn some of my own candi syrup for two of them and using some tettnang or hersbrucker hops.
Any thoughts or suggestions? I gather from my reading that roasting gluten free grains is still in the experimental stage, even among hardcore gluten free brewers, and I'm certainly an admitted noob. I'm interested in hearing what anyone has to say...