I'll have a big roast in the oven for a couple of hours, with the juice collected in a glass jar, put in the freezer so the "top" will form the fat which I discard and the gel (gelatin/gravy?) underneith. Now, about that "gel" - how would it compare, in composition, to say, Great Lakes Beef Gelatin, or even the hydrolysate stuff? Sure, nothing beats the real McCoy, but I'm really curious.