I made beef stock for the first time last weekend. (I know, I know, give me a gold medal.) After simmering and straining, I put the stuff out in the garage to cool (gotta love Minnesota winters.) When I went back to it the next day to remove the layer of fat, what was left underneath was gelatinous like jello. Is this normal? I understand that the collagen in the bones could cause jelling, but I was expecting liquid. Does this happen to you?