Does cooking food impact the spoilage/decay rate?
In Don't Starve, cooking food can have a variety of effects on the restorative and degenerative properties of food.
I've seen people say to keep it in crock pots until ready to use to prevent spoilage, but this is not great when you have low research. And, I've seen mods that prevent spoilage, but that just isn't what I want to do.
But, does a cooked item last longer than the raw food?
It depends on the item. Most fruit and vegetables will decay quicker after cooking- for example, cooked carrots last 6 days instead of 10. On the other hand, most meat will last longer- usually 10 days instead of 6.
Cooking an item does half the level of spoilage- for example a 50% spoiled item will only be 25% spoiled after cooking. This means that, if you have the inventory space, even meat should only be cooked when you intend to eat it.
For example, a morsel will fully decay in 6 days. Leaving it 3 days will result in it decaying by 50%- if you then cook it it will be 25%. On the other hand, cooking it immediately and leaving it 3 days will result in it being 30% decayed.
Cooked food will usually decay slower than raw foods. Also, cooking a food halves the decay, so it is to your benefit to wait until a food is almost rotten before cooking it, as that will give you the maximum increase in quality.