After just one day of growth in PCB all strains increased in viable cell loads reaching average values of 7.24 log cfu mL 1, except P. fragi 23A, that displayed only 3.90 log cfu mL 1 (Table 1).
However, all strains showed a plateau in growth starting from day two (8.36 log cfu mL 1, on average).
The addition of 10 mg mL 1 of BLF in PCB completely inhibited the growth of R. aquatilis 19B, P. fragi 23A and E. coli K12 up to day seven of incubation. By contrast, both S. proteamaculans 19A and A. salmonicida 22DB resulted resistant to BLF, confirming the results of preliminary assays. P. gessardi 2A resulted partially inhibited as this strain grew constantly even though its viable cell counts were always lower than those of the un-supplemented control from 1 to 3 log cfu mL 1, depending on the time of sampling (Table 1).
A similar inhibition pattern was registered when PCB was amended with the LFH, even though a higher inhibition activity was observed on Pseudomonas 23A (Table 1).
In order to verify the transferability of the results from the laboratory growth conditions to those occurring in HM Mozzarella cheese, the experiment was repeated replacing commercial medium with governing liquid and decreasing the temperature of incubation from 30 C to 4 C.