Expired panko bread crumbs A couple of days ago, I used some expired panko bread crumbs (expired by at least 5 months) for chicken tenders. They had this bad stale oil smell to them and I decided to take a risk. They had previously been opened but I'm very careful in closing them back up and storing them in a cool dry place.

As the first step of the recipe, I lightly fry the panko bread crumbs in a little oil and that removed that bad oil smell instantly. The chicken tenders smelt and tasted fine as well.

I read this and it says that bread crumbs don't spoil, the thing is 
though that it definitely smelt pretty bad. So, is the stale oil smell or the expiry something to worry about?
That "stale oil" smell was probably the small amount of fats in the crumbs going rancid and forming butyric acid. I usually do not cook with anything that smells bad, my thought is that it just isn't worth the risk, but risk tolerance varies.