Gelatin is made from the collagen in cow or pig bones, hooves, and connective tissues. all animals are made up of about a third collagen. Manufacturers grind up these parts, chemically treat them to break down the cellular structure. this releases collagen. then the whole mixture is boiled. as a result the large collagen protein ends up being partially broken down, and produces a product known as gelatin. this is easily retrieved as it need only be skimmed from the surface of the soup.