I work at a brewery and bring home spent grain for my girls, THEY GO CRAZY OVER IT. I have to ration it because they will eat too much and get runny poop. To keep it from souring, I just separate it into smaller containers and freeze it, when one container is almost gone I put one from the freezer into the fridge to thaw. My girls come running when they hear the container open, It is their favorite treat...It is also good for the compost if it does sour, your not wasting it if you throw it into the compost pile. I have also heard it is great to toss it right onto the garden, but I have not had any left over to try that, the girls gobble it right down. The brewery I work for donates their spent grain to a local farmer for his pigs, one of the brewers takes some for his Chickens and I take some for mine. If you have a local brewery, you should ask them about it, if their not donating it, it will end up in the land fill when it could be making your chickens very happy. I am sure they will be very happy to give it to you if they are not giving it to someone already.