I strongly suspect McRib meat is NOT "ground pork", but rather more of a "pink-slime" concoction that was derived by chemists in a lab; inedible save for some ammonia treatment.
I have never eaten that crap and I never will.
Jesus christ not this again.
I have no intention of "defending McDonald's" nor do I really particularly care for the McRib. I got it a few years in a row but I've shied away from it as of a few years ago, as the last time I had it I determined I'd either rather have fast food burger or whole cuts of pork - the McRib just wasn't doing it for me anymore.
But, unless McDonald's is challenging the FDA and has the biggest set of balls a corporation could ever have, there is absolutely no pink-slime product in the McRib.
Why? Because they clearly do not list mechanically separated pork on the ingredient list.
There is a BIG difference between taking stuff like offal, shoulder cut scraps, and probably scraps of other cuts and blending it together... compared to the true mechanically separated product, which includes all the connective tissues and whatnot.
It's absolutely illegal to use mechanically separated pork (or any meat) in a product and not CLEARLY list it as mechanically separated.
It's just about guaranteed the McRib and similar rib patties have stuff like tripe and various scraps, but it is definitely of a higher class of meat than mechanically separated. It should also contain no ammonia or anything to wash the meat. It could, that's not required to be listed - but that's typically only a step utilized in the production of MSM products.
You're more likely to pick something up at the grocery store containing MSM products (especially anything from Tyson foods, iirc), than you are to get anything from fast food joints with it. There are a host of OTHER concerns, very valid concerns, like how many and what preservatives and anti-foaming and bleaching agents are used - but the fast food industry got grilled for their use of MSM products, and they've also largely, if not 100% completely, moved away from using them. McDonald's is chief among the brands, at least within the US (they have a different menu in many countries, local products/tastes), to have gone 100% MSM-free. As I said, there are many reasons to dislike McD's, but MSM is not a valid reason at this time.