PART A) Gelatin is processed collagen that comes from the bone and joints of animals. Collagen is a structural protein consisting of a triple helix – three polypeptide chains wound around each other. The directions on a box of Jell-OTM brand gelatin require that the package contents (containing gelatin) be added to hot water, mixed to dissolve, and then cooled. Describe the structure of collagen before, during, and after heating and cooling. Also explain why once Jell OTM is cooled it has a jiggly semi-solid consistency.

PART B) It is also possible to make Jell-OTM with added pieces of fruit. The directions on the box include the following: “Chill until slightly thickened, and then add 1 to 2 cups cooked or raw fruits. Fresh or frozen pineapple must be cooked before adding”. If the pineapple is not cooked, the gelatin will not set properly. Pineapple belongs to a group of plants called Bromeliads. Pineapple contains a protease called bromelin. Explain why the pineapple must be cooked and how uncooked pineapple prevents gelatin from setting.