Gelatine
Gelatine is obtained from pig skin, bone and hide. Animal protein is in high demand from an enormous range of industries and is used, for example, in the production of foodstuffs, pharmaceutical products and even in the production of photographs and films. GEA Westfalia Separator supports the recovery of gelatine by separating extraction residues, together with defatting and fine clarification of thin gelatine.
Gelatine is a highly pure form of animal protein. It is based on collagen. Collagen is found in especially high concentrations in gelatine raw materials such as bones, skin and connective tissue. Between five and eight kilograms of raw material are needed for a kilogram of gelatine.
There are two basic types of pre-treatment in the production of gelatine: an alkaline process for Type B (basic) gelatine, and an acid process from which Type A (acid) gelatin is obtained.
Simplified representation of the gelatine process
The process for acid gelatine extraction is primarily suitable for pig skin. The process is based on swelling and extracting raw collagen by the action of a strong acid and subsequent washing out. Once pre-treated in this way, hot water is added to the materials and they are subjected to discontinuous staged extraction.
The resulting gelatin solution subsequently has to be freed from fat residues from the raw material and from small fibers, because no fat particles may be present in gelatine. In a single step, separators from GEA Westfalia Separator simultaneously extract the fat and also clean solid particles which can be spun off.
For subsequent fine clarification, diatomaceous earth filters are frequently used in which the pollutant kieselguhr is used as a filter aid to retain fine contaminants. High-performance clarifiers from GEA Westfalia Separator can replace kieselguhr filtration and extend the lifetime of downstream sheet filters.
Specific residue treatment
In particular when extracting from pig skin, fat and insoluble solids are left. To treat these residues further, both on economic grounds and also with a view to process optimization, GEA Westfalia Separator decanters can be used in a subsequent extraction stage. The 3-phase decanters separate the suspended residues into pure fat, thin gelatine and solids. Whilst gelatine can be returned to the process, the other discharged products can be sold as technical fats or protein meal.