How do I get a softer crust?
I am trying to bake a soft sandwich loaf from sourdough, using this recipe: http://www.wildyeastblog.com/2011/07/14/soft-sandwich-sourdough/  but I don't have any powdered milk, so I leave that out. Also, I usually am scaling the recipe to make more than it calls for, and using a slightly higher hydration. The recipe makes about a 64% hydration dough, and I usually keep mine at about 70% hydration (counting only the flour and water, because I don't know how to calculate the other ingredients for hydration). It almost always turns out wonderful bread, but the crust is thick, and when I store it, it turns tough. I was wondering if there is a way to get a lighter (as in thinner) crust on my bread, or at least a crust that is not tough. Is that little bit of milk powder the magic ingredient that does that? I know I've read that milk does make the bread softer, because it inhibits some of the gluten formation. Help me out here, please! Susan, if you happen to be around, tell me what I'm doing wrong with your recipe!
One thing I have already tried is baking at a lower temp for a longer time. I've also tried baking with and without steam.