Gelatin, unflavored is a powdered thickening agent made from pure protein produced from beef and veal bones, cartilage, or pork skin. When added to liquid the gelatin congeals the ingredients into a clear mass. Use for molded dishes, salads and gelatin desserts and chiffons.
Knox is probably the most common brand in the U.S. Purchase this product in most any grocery store. It has a very long shelf life so don't worry about keeping in for a couple of years in your pantry.