Physical properties of collagen

About gelatin

gelatins physical properties

Gelatin is a protein derived by a mild partial hydrolysis at relatively low temperature from a parent protein, collagen. In an aqueous solution it is a hydrophilic colloid. It is almost tasteless, odorless, vitreous, brittle solid and usually faintly yellow in colour.

Two of its most useful properties are gel strength and viscosity, on which it is mainly assessed. It is also assessed by color and clarity.

Ash, moisture, SO2, trace metal and microbiological content are maintained in compliance with pure food regulations.

Three main classes of material are commercially and technically feasible to manufacture gelatin:

pig skin
beef skin
bone

Gelatin derived from pigskin is usually referred to as type 'A' gelatin. Type 'B' gelatin is derived from beef skin.
Typical specifications for edible gelatins are:

	Type A	Type B
pH	3.8 - 5.5	5.0 - 7.5
Isoelectric Point	7.0 - 9.0	4.7 - 6.0
Gel strength (bloom)	50 - 300	50 - 300
Viscosity (mps)	15 - 75	20 - 75
Ash (%)	0.3 - 2.0	0.5 - 2.0