stock: to gel or not to gel

[Guest guest]

I can't figure out what's responsible for making my stock gel or not.

Sometimes the grass-fed meats make gelatinous stock, and sometimes they

don't. Yesterday I used organic chicken legs from the health food store,

that came from a small local farm, didn't specifically say what feed, but I

figured the meat might be better quality than most. Didn't gel. Sometimes

I've used factory farmed but antibiotic and hormone-free meats from the

supermarket, and that sometimes gels, sometimes doesn't. I can't seem to

see any pattern. Any ideas?

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