Antibacterial effect of the lactoperoxidase system on psychotrophic bacteria in milk.

Activation of the antibacterial lactoperoxidase system in milk, i.e. increasing the thiocyanate concentration to 0.25 mM and adding an equimolar amount of H2O2, results in a substantial reduction of the bacterial flora and prevents the multiplication of psychrotrophic bacteria for up to 5 d. This treatment has no effect on the physico-chemical properties of milk and does not lead to the accumulation of resistant bacteria. The practical application of the lactoperoxidase system in prolonging the storage period of raw milk at low temperatures is discussed.