In the case of PL, the treatment conditions were investigated
from a very mild energy dose (3
104 J/m2 per side) to the
maximum value (1.2
105 J/m2 per side) allowed for surface
decontamination of food (FDA, 1996).
The results show that an energy dose of 3
104 J/m2 per side did
not significantly increase the antimicrobial effect of the coating
alone (Fig. 1b). In contrast, treatments at 6
104 and 1.2
105 J/m2
per side reduced the microbial load of 1.4 and 2.5 Log cycles,
respectively, with respect to control.
In particular, for further studies the treatment with an energy
dose of 1.2
105 J/m2 per side was selected, which caused areduction of the microbial population from 6.2 Log CFU/g to
3.7 Log CFU/g.