Bacteria Removal Separators for Milk and Whey

BACTERIA REMOVAL SEPARATORS FOR MILK AND WHEY

Dairy products can become heavily contaminated by bacteria and spores, somatic cells and non-milk constituents. This makes it all the more important to remove impurities from the raw and vat milk as well as the whey efficiently, a job that is reliably performed by the bacteria removal separators from GEA.

Application spectrum ranges from the one-stage, two-stage and special bacteria separation from drinking milk through variable bacteriaseparation to cheese-making milk, right up to treatment of the whey concentrate.

Increased protein yield with GEA proplus

Optionally, the bacteria removal separators can be equipped with the proplus system. With proplus it is possible to extend the ejection intervals during production up to six-fold compared to conventional bacteria removal separators. The result is a significant boost in protein yield from the raw milk used by means of consistent loss minimization of up to 75 %. In addition, there is a decrease in costs for waste water, maintenance and wear.

Optimum design for the efficient removal of spore formers

The bacteria removal separator separates in particular spore formers such as Bacillus cereus, heat-resistant up to 128 °C and cold-tolerant at the same time, which negatively impact the shelf life of the drinking milk due to sweet coagulation. A large number of cheese defects can likewise be prevented effectively through the application of bacteria removal separators.

The use of nitrate is also largely superfluous or can be dispensed with completely. Due to the higher specific gravity of the spores compared to the raw milk and skim milk, they can be removed from the milk extremely efficiently with the aid of bacteria-removing centrifuges. The design of the centrifuge – the feed, disk stack and centripetal pump in particular – is configured optimally for this task. Additionally, every GEA bacteria removal separator is equipped with a so-called recirculation system. Up to 3% of the feed volume is tapped off as carrier liquid and recycled back into the feed. In this way, the spores can be reduced by up to 99%.

Fresh milk with a longer shelf life thanks to GEA prolong

The double bacteria removal with two bacteria removal separators reliably removes somatic cells, bacteria and spores from the milk. The result: the first fresh milk that combines natural flavor and full vitamin content with a long shelf life. The GEA prolong process can be integrated profitably into a broad spectrum of dairy concepts because the double bacteria removal can be used without difficulty in the production of further products such as cheese and milk powder.

On account of the design features mentioned, it is possible to apply the prolong process developed by GEA and already successfully in use in several dairies. There is no further heat treatment apart from the necessary pasteurisation (IDF standard with no excessive heat load). When milk is temperature-treated to inactivate bacteria and spores (e.g. UHT, ESL) undesired side effects such as changes in flavor may occur and process costs increase.

Bacteria separation of whey

Bacteria separation is likewise recommended downstream of the cheese-making process since the whey are processed at temperatures conducive to optimal bacterial growth.

Following bacteria separation, the drip whey can be remixed with the other whey instead of being used as animal feed or being disposed of altogether as was previously the case. Due to the long retention times and optimum growth temperatures, intense bacterial growth also takes place in the filtration equipment for concentrating the whey. When, for example, serum proteins are to be recovered from the clarified and skimmed milk in concentrated form (WPC, whey protein concentrate) by means of ultrafiltration, many dairies are meanwhile using bacteria removal separators. To meet the most stringent quality requirements, GEA bacteria removal separators can be used effectively for whey as well as concentrates. To sum up, efficiency levels of up to 90 % and often more can be achieved in relation to the total germ count.