Physical & Chemical Properties
Gelatin is nearly tasteless and odorless.
It is a vitreous, brittle solid faintly yellow in color. Gelatin contains 8-13% moisture and has a relative density of 1.3-1.4. Gelatin stored in air-tight containers at room temperature remains unchanged for long periods of time.
Collagen may be considered an anhydride of gelatin. The hydrolytic conversion of collagen to gelatin yields molecules of varying mass: each is a fragment of the collagen chain from which it was cleaved. Therefore, gelatin is not a single chemical entity, but a mixture of fractions composed entirely of amino acids joined by peptide linkages to form polymers varying in molecular weights from 15,000 to 400,000.
Since it is derived from collagen, gelatin is properly classified as a derived protein. It gives typical protein reactions and is hydrolyzed by most proteolytic enzymes to yield its peptide or amino acid components.