Starter Cultures Freezing
Manufacturers of starter cultures for yoghurts, cheese, etc. freeze the culture material in blocks and then dry it in freeze dryers. Sometimes the frozen blocks are also processed to granules to shorten the drying time. However, the survival rates of the cultures are not optimal with this method.
An alternative is the technique of pelleting. Here liquid or paste-like substances are fixed as pellets with the help of a cryogenic cooling medium. The process uses both the evaporation enthalpy of liquid nitrogen as well as the cooling energy of the cold gas.
Liquid nitrogen (N2) is the preferred cryogenic cooling medium.
Compared to conventional cooling processes pelletizing offers, in particular, the following advantages:
- High survival rate of biological substances
- Variable adjustment of the freezing capacity through module technology
- Good and uniform product quality
- Low nitrogen consumption
The Cryogen-Rapid Pelletizer from Messer fixes liquids in the form of frozen pellets at very high freezing rates and with a homogeneous quality.
The modular construction of the Cryogen-Rapid Pelletizer makes it possible to adapt the performance of the machine to its requirements. There are applications for the Cryogen-Rapid Pelletizer in the food industry, for example in the production of ice-cream. Furthermore, it is highly suitable for biological and pharmaceutical products, such as manufacturing starter cultures for yoghurt.