I don't know about the cheesy smell. Hard to describe rancid fat. Best to have what you know for sure is fresh, and then start comparing it. For me, there is a definite energy loss when the fat is old. My guess is that all animals killed in the wild, but other animals or humans,, the fat was eaten first. This whole 'pemican' revelation to me is nothing but a way for people to survive in the winter months, and has little to do with optimum health,, as regards ingesting rancid fats.