Physical properties

Edible gelatin is white or light yellow-brown, translucent, slightly shiny chips or powder, almost odorless and odorless.It is insoluble in cold water, but can absorb 5 times the amount of cold water and expand and soften.Dissolve in hot water and form a gel after cooling.It is soluble in an aqueous solution of polyols such as acetic acid, glycerol, propylene glycol, etc.It is insoluble in ethanol, ether, chloroform and most other non-polar organic solvents.

Chemical properties

Edible gelatin has weaker coagulation power than agar, and does not coagulate when the concentration is below 5%.Usually a gel is formed with a solution of 10% to 15%.The gelling temperature varies with the concentration, the type of coexisting salts, the pH of the concentrated solution and other factors.The difference between the dissolution temperature and the solidification temperature is very small, it dissolves at about 30℃, and solidifies at 20~25℃.Its gel is softer than agar, elastic, and has a soft taste.Its aqueous solution is boiled for a long time, and its properties change due to decomposition. After cooling, it no longer forms a gel. If it is reheated, it becomes protein and protein.If the gelatin solution is affected by formaldehyde, it becomes an irreversible gel that is insoluble in water.