2. Bactofugation is the process of removal of microorganisms from
milk using centrifugal force.
It is a special form of separation of microorganisms, mainly spore
formers(Bacilli/Clostridia) to enable milk to be sterilized at lower
temperature-time combinations.
Most of the microorganisms are inactivated by pasteurization.
However, the highly heat resistant spores survive pasteurization.
They can lead to significant quality defects in hard cheese, semi-
hard cheese or long-life products due to proteolysis, lipolysis and
gas formation.
Therefore, bactofugation is mainly used in the manufacture of
these products.
Introduction
3. To improve hygienic quality of milk
To avoid heat resistant bacteria without resorting to excessive
heating
To ensure exceptionally high degree of bacteriological purity in
milk
Objectives
4. Bactofuge are special nozzle clarifying separator with high
separation precision that can remove microorganisms from milk
based on their density difference (skim milk – 1.036; bacteria –
1.07 – 1.13 g/cm3).
Separated micro-organisms are concentrated on the periphery of
the bowl and the small portion of such discharged milk, highly
enriched with the bacteria (bactofugate) is thrown outside via
nozzles, and then collected in the sludge discharge pipe. The
bactofugate which still corresponds to 2 -3 % of the treated milk
may be sterilized separately and added back to the bactofuged
milk to avoid the losses of milk solids (Fig. 1).
Bactofuge and its design
6. Use of bactofuged cheese milk prevents swelling in certain
cheeses which may be caused by heat resistant butyric acid
bacteria. Removal of bacteria without pasteurization enables
cheddar cheese production with more typical cheese flavor.
The severity of heat treatment can be reduced in sterilized
milks.
In cream, defects caused by heat resistant Bacillus cereus can
be avoided.
Advantages
