As far as I know, the spoiled meat can only appear in as loot, at least I haven’t seen any of my meat spoil personally. I think it might be interesting to add mechanic that would cause meat, both cooked and uncooked to spoil. I don’t think raw meat that’s been sitting in the same box with leather, animal fat, and what ever else happens to be in there is going to last cooked or not. Maybe add some kind of timer on uncooked and cooked meat that will cause it to spoil after a certain amount of time. IMHO, food should be a little more important of a resource as well.
To follow with this idea, how about a little change in some of the food setup. First of all, hunger be a little more active, and have a greater variance depending on actions, this way putting food a little more forward rather than an after thought. with the idea of changing uncooked and cooked food to be able to spoil, another method may be used for cooking. Curing and smoking. This can be done using wood in an outdoor smokehouse, the food takes longer to cook, only overcooks after a much longer time, but doesn’t spoil. It also does not provide as much nutrition as normal cooking, and due to the increased salt content, actually removes from the water rather than adding to it like other food does. This also follows with the theme of having to protect bigger production areas outdoors, eg large furnaces.