Collagen is a large molecule protein found in the connective tissue of animals. Foods that contain a lot of collagen include animal dermis, poultry wings and claws, animal calves, animal tendons and fascia, and animal cartilage and bones. 1. Animal skin: animal skin (pig, cow, sheep, etc.), poultry skin (chicken, duck, goose, etc.), as well as fish skin, etc. contain a lot of collagen, and can be made into soup or jelly. 2. Poultry wings and claws: by the bones, tendons, dermis and other components of the wings and claws, muscle and fat content is small, the largest content of collagen. Such as chicken wings, chicken claws, duck paws, duck wings, goose palms and so on. 3. Animal calf: tendons, fascia and dermis covering the bones contain a lot of collagen. Such as pig calf, sheep calf, cow calf and so on. 4. Animal tendon and fascia: this position is mainly collagen connective tissue, rich in collagen. Such as beef brisket, beef tendon, pig’s feet, etc.. 5. Animal cartilage and bones: this type of food is widely available, such as pigs, cows, sheep skulls, leg bones, spinal bones, duck skeleton, chicken skeleton, fish head, fish bones, etc. contain a large amount of collagen, especially cartilage containing more collagen, this type of food is mostly stew-based. In addition to the above categories, also contains a large number of collagen gelatine, gelatine, also known as fish maw, is taken out of the swim bladder from the fish belly, rich in protein, gelatine and so on.