, colorless to light yellow solid, into powder, flakes or lumps. It is glossy, odorless and tasteless. Relative molecular mass of about 50000 ~ 100000. relative density 1.3 ~ 1.4. insoluble in water, but when immersed in water, it can absorb 5 ~ 10 times the water and swell and soften, if heated, it will dissolve into a colloid, cooled to below 35 ~ 40 ℃, it becomes a gel; if the aqueous solution is boiled for a long time, it will change in nature due to decomposition, and it will no longer form a gel when it cools. Insoluble in ethanol, ether and chloroform, soluble in hot water, glycerol, propylene glycol, acetic acid, salicylic acid, benzene dicarboxylic acid, urea, thiourea, thiocyanate and potassium bromide. The concentration of this product is not solidified below 5%, and usually forms a gel with a 10% to 15% solution. The temperature of gelation varies with concentration, ****existing salts and pH. Viscosity and gel strength vary according to relative molecular mass distribution, and are affected by pH, temperature and electrolytes. If the solution of this product meets formaldehyde, it becomes an irreversible gel that is not soluble in water. This product is easy to absorb moisture, due to bacteria and corruption, should be careful when preserved. When hydrolyzed, various amino acids can be obtained.

Difference with collagen

Gelatin is a class of proteins obtained by partial hydrolysis of collagen, gelatin and collagen have homology. Collagen has a rod-shaped three-stranded helix structure, when it is partially hydrolyzed to prepare gelatin in the process of this three-helix structure of the collagen partially separated and fractured. The amino acid composition of gelatin is similar to that of collagen, but the composition may be different due to differences in pretreatment.

Physical and chemical properties of gelatin

Gelatin is a product of collagen denaturation, belongs to the category of protein macromolecules, it has similar characteristics with protein macromolecules, but due to the specificity of the molecular structure, determines its physical and chemical properties and unique.