Will Toasting Flaked Grains Effect Potential?

[AnOldUR]

Toasted some flaked rye (5% of grain bill) yesterday. One hour at 350 degrees. Browned nicely, didn't stick to the cookie tray and smelled great. I got a few points less efficiency than expected. Does toasting flaked grain cook off some of the starches and reduce potential?

 

[JLP]

I don't have the official answer, but it would make sense that it would reduce the potential of the grain. It is basically rekiling the malt to make a darker and more flavorful version of it, and cooking the starches to a less convertible state is a biproduct.