What kind of check would it be to identify meat?

Question

If the characters were presented with some cubes of cooked meat, what kind of check would be necessary for them to make in order to determine what kind of animal or creature it came from.

For example, if it upon cursory examination appeared to be ham cubes, but was really human meat cubes, what skill or knowledge check would be relevant to tell the difference? Profession: butcher to tell it's not ham? Knowledge: nature?

For some more context, I want the players to find a magic bag that fills with cubes of cooked meat that appears to be ham, but is actually cubes of human flesh with some way for them to eventually find out that they've been eating people "all this time" without knowing it.

Update: If anyone is curious, as per the answer I've accepted, I've decided to go with these perception rules for it:

DC 5: you think it's ham
DC 18: you know it's not ham, but you're not sure what it is
DC 28: you know it's human.
Any character that has knowingly eaten or smelled cooked human meat a +20, and any one with a butchering experience a +5 towards the DC 18 check.

Answer 1

Perception seems to fit the bill. It's a DC 5 check to determine whether food you're about to eat is spoiled; at higher DCs, one should be able to tell whether the meat they're eating is actually pig or lamb or…something else less salubrious. Plus, it's tied to Wisdom and the senses, both of which would be in use here.

Answer 2

Profession(Cook, butcher or similar) or survival would be useful to identify the normal kinds of wild meat game (for survival) or the most usual types of meat used in cooking (for the professions), or to determine that a certain kind of meat is not one of the usual types, but not necesarily be able to identify it.

Honestly, unless the characters had knowingly consumed,prepared or at least found cooked human meat before, it would be truly difficult for them to recognize the origin of the meat using only their senses. It would be easier for them to know by using magic. Or by analizing the posible consequences of the meat consumption...

Answer 3

Given that pig and baboon heart and muscle can be, and in fact was, successfully transplanted into humans, and they resume their work (see Xenotransplantation), I do not believe that anything short of magic or epic-level skill check could be used to distinguish so small pig ham piece from equally small human ham piece.

Pigs are used in xenotransplant experiments because their tissue structure and even large-scale organ structure is similar enough. Pig heart have all it's pipes in exactly right places. For something as simple as gluteal, recognizing would be next to impossible. Only significant difference at tissue / organ level is immunologic system - something hardly known at all in most of high fantasy worlds. And certainly not something you can examine once meat is already cooked.

For taste, German convicted cannibal Armin Meiwes said:

The flesh tastes like pork, a little bit more bitter, stronger.

And he was experienced guy, who ate knowingly and actively tried to learn the taste differences. So taste checks are probably out of the question, too. Especially if meat is seasoned.