I cleaned out my pantry in the winters to help feed the chickens, just as you are doing, and found they would eat just about any prepared food. In winter, protein is a big must, so I would even let them pick at bones, or cook up fish skins. I also let them stop laying, to do what they naturally would, thinking that they might need less food if I did.
A ping pong ball in the water keeps it liquid quite a bit longer.
You've got me missing my chickens.