Compost is, almost by definition, not fresh, so yes, go right ahead and use them. I can think of few things that are rotting in the back of the refrigerator that would not be beneficial in a compost pile. Soured
milk, moldy bits off a block of cheese, some vegetables that were steamed a week ago and are now slimy, I throw anything of that sort into the compost tea
bucket. Since I am the undisputable top of the household food chain, anything I reject has to go all the way to the bottom (i.e., the composting bucket) before that biomass can start its long climb back up.