From raw material to gelatin
1.Pretreatment
Before processing, the raw materials are thoroughly cleaned. There are two basic processes, depending on the raw material:
Acid process - for gelatin type A: The raw material (mostly pigskin) is subjected to a 24-h conditioning process. This involves treatment with acid. After this, the gelatin can be extracted.
Alkaline process - for gelatin type B: Here, the raw material (either ossein or bovine hide) is subjected to several weeks of treatment with alkali. This enables the collagen structure to be gently transformed. The collagen it contains, now softened by the pretreatment, can then be extracted using warm water.
2. Extraction
The materials are subsequently treated with a warm water extraction process to remove the gelatin. The first gelatin extracts, obtained at relatively low temperatures, are quite firm and have a light color, containing approximately 6% gelatin. The remaining material is treated with fresh water but at a higher temperature. This sequence is continued until all the gelatin has been extracted.
A variation of this classic extraction process is the so-called continuous process. Here, warm water and the raw materials are continuously fed into the extraction vessel and the gelatin solution is continuously removed. The desired properties of the gelatin can be adjusted by varying the temperature and pH.
3. Purification
Residual traces of fat and/or insoluble particles are removed from the gelatin solution in high-performance separators. Precoat filters using Kieselgur (diatomaceous earth) then remove fine particles. This is followed by filtration through cellulose plates, as used in the beverage industry, and a final ion exchange purification step to remove any salts.
4. Concentration
Multi-stage vacuum evaporators gently remove some of the water from the solution: the gelatin becomes viscous and honey-like in consistency. This highly viscous solution is then passed through cellulose polishing filters to remove any fine particles that may remain.
5. Drying
After that, the gelatin solution is heat-sterilized, then cooled and allowed to set. The gelatin is now in the form of "gelatin noodles" which are dried with sterile and filtered air. At the end of the conveyor belt, the now hard and brittle gelatin is broken up, milled and stored in the warehouse. Individual batches are only released for further use pending the successful completion of physical, chemical and bacteriological testing in the lab.
6. Milling, sieving, blending
Milling, sieving and blending are the final three processing steps. Here, the dried gelatin is customized to the requirements of individual customers. Once filled into silos, Big-Bags, sacks or bags and after final release from the lab, the products are transported to the customer.