It is a heterogeneous mixture of water-soluble proteins of high average molecular weights.
Gelatine is obtained by hydrolysis of collagen by boiling skin, ligaments, tendons, etc.
Its production differs from that of animal glue in that the raw materials are selected, cleaned, and treated with special care so that the product is cleaner and purer than glue. Gelatine swells when water is added and dissolves in hot water to form a solution that sets to a gel on cooling. It is used in photographic emulsions, pharmaceuticals, adhesives, and in jellies and other foodstuffs.