Starter cultures are literally on everyone’s lips. The helpful micro-organisms are employed in the most diverse fields of the food industry and also as a probiotic dietary supplement. Examples are the dairy, meat and bakery industries, in the production of fermented vegetables, in the production of wine and beer and in the animal feed industry. Starter cultures are cultivated from undefined, empirically produced species to attain a predictable and reproducible quality and quantity of the product.
The production of starter cultures can be divided into two sections. After cultivation in fermenters, the bacteria must be processed and separated from the fermentation solution. This consists of the nurtured lactobacilli and the remainder of the nutrient solution including the produced lactic acid. Firstly, the micro-organisms are separated and concentrated from the liquid phase. Nozzle and self-cleaning disc separators in steam-sterilized design are available for this step of the process. The concentrated lactobacilli then pass to a freeze-drier. Finally, the cultures are packaged under oxygen exclusion and stored at low temperatures. This retains their activity for months before they are processed, e. g. as “live cultures” in probiotic yogurts.
Sterility and Careful Treatment
The careful treatment of the living micro-organisms, sterility and a high separation efficiency are prerequisite to the economical, reliable and efficient processing. The separators from GEA employed in this production process are therefore equipped with hydrohermetic product feed systems which minimize the shear forces when the product enters the bowl and therefore guarantee the high vitality of the cells.