Gelatin is derived from collagen, by partial hydrolysis.
Collagen is present in three materials suitable for producing gelatin on a commercial scale:
- pork skin,
- cattle skin, and
The three raw materials are not mixed for processing.
As these materials are by-products of the meat industry, gelatin plants are often found in areas of large cattle and hog populations, and often in close proximity to abattoirs and meat packers.
Each type of raw material undergoes a different pre-treatment (conditioning) process.
Regardless of which material is used, it is first cut, washed and cleaned so as to remove as much of the non-collagenous material as possible. Depending on the source material, the gelatin derived from this process is either Type A or Type B.
Type A gelatin is produced from an acid process. It is mainly applied to pig skin, in which the collagen molecule is young.
Type B gelatin is formed form an alkaline and acid process. It is mainly applied to cattle skin and bone, in which the triple-helix collagen molecule is older, more densely cross-linked and complex.