text: what is jello made of? i heard it was made of ground up bones. the production of gelatin starts with the boiling of bones, skins, and hides of cows and pigs, a process that releases the protein-rich collagen from animal tissues. the collagen is boiled and filtered numerous times, dried, and ground to a powder. because the collagen is processed extensively, the final product is not categorized as a meat or animal product by the federal government. very strict vegetarians avoid gelatin entirely, but more permissive vegetarians have no problem including jell-o in their diets.  jell-o products account for about 80 percent of the gelatin market.  popular belief has it that gelatin comes from horses' and cows' hooves. kraft, the maker of jell-o, asserts that hooves do not contain the necessary collagen and therefore are not used in the production of their jell-o brand gelatin product.