Gelatine is a protein derived from the collagen content in pig skin, cattle hide or animal bones. Gelatine is widely used as a binder and gelling agent in the food industry, and is also used in pharmaceuticals and cosmetics. The standard process for gelatine production involves clarification, fractionation (in which salts and other related substances are removed using ultrafiltration technology), concentration by evaporation, and sterilization.
After extraction of the soluble water proteins, it is very important to clarify the diluted gelatine solution to a minimum of fat and suspended solids. Centrifugal force is a natural choice for such clarification, and Alfa Laval clarifier centrifuges provide the flexibility to match your specific gelatine requirements.
After final clarification in diatomaceous earth filters, the gelatine solution is ready for fractionation, where salt and other related substances can be removed by ultrafiltration. Ultrafiltration also acts in the same way as a pre-concentrator.
Alfa Laval ultrafiltration technology can be configured to comply with any customer specification and the final concentration depends on the gelatine type, the bloom figure and the viscosity of the gelatine. Alfa Laval membrane filtration for gelatine is carried out in a continuous module at a controlled temperature.
Final concentration takes place in an AlfaVap rising film evaporator system. Retention time and temperature profile have a strong impact on the end product quality.
The AlfaVap evaporation system provides a very short product retention time, combined with a very gentle temperature profile, which together ensure superior product quality and colour.
To ensure the best possible product quality, gelatine should be sterilized at temperatures around 130–140°C for 3–4 seconds. Alfa Laval provides sterilization modules based on direct steam injection or indirect product heating. In both cases, the product retention time is extremely short and the energy used in sterilizing the product is efficiently recovered for pre-heating the incoming product.