Bacterial Starter Cultures

A fermentation starter or starter culture is a preparation that’s used to kick-start the fermentation process in a number of diverse industries, from food & renewables to biotechnology and pharmaceutical.

In the pharmaceutical industry, bacteria are used to produce antibiotics, vaccines and medically useful enzymes. The biotechnology industry uses bacterial cells for the production of biological substances that are useful to human existence, including fuels, foods, medicines, hormones, enzymes, proteins and nucleic acids, resulting in the development of human hormones such as insulin, enzymes such as streptokinase, and human proteins such as interferon and tumor necrosis factor. These products are used for the treatment of a various medical conditions and diseases, including diabetes, heart attack, tuberculosis, AIDS and SLE (lupus).

Cultivation, Processing, Harvesting

Starter cultures are derived from undefined, empirically produced species to attain an end-product with predictable and reproducible quality and quantity characteristics. The production of starter cultures can be divided into two sections. 

After fermentation, the bacteria must be processed and separated from the fermentation solution, comprising the cultured micro-organisms and the remainder of the nutrient solution. First, the bacteria are separated from the liquid phase and concentrated: nozzle and self-cleaning steam-sterilizable disc separators are available for this step of the process. 

The concentrated culture is then transferred to a freeze dryer (lyophilizer) and dried. Finally, the cultures are packaged under airtight conditions and stored at low temperatures. 

Aseptic Processing

The careful treatment of the active culture, sterility and high separation efficiencies are prerequisites for the economical, reliable and efficient processing of bacterial starter cultures. As such, separators from GEA are equipped with hydrohermetic product feed systems that minimize the shear forces experienced when the product enters the bowl, which maintains the viability of the cells.