In the case of HHP treatment, the microbial population was
initially decreased to 5.3 Log CFU/g, and decreased continuously
over storage time. The
final microbial concentration in the HHP-
treated sample was 3.6 Log CFU/g on day 14. This fact suggested the
occurrence of sublethal cell damage as a consequence of HHP
treatment, probably due to a partial loss of cytoplasmic membrane
functionality or damage to the gram-negative outer membrane
after the high pressure treatment. Therefore, partially damaged
cells may either recover their viability and survive after the
treatment or die. In addition, the sublethally injured cells may
enhance their sensitivity to inhibitors such as sodium chloride, bile
salts, ingredients of selective media or antimicrobial agents,
enabling the design of combined processes that increase the
effectiveness of pressure processing (Somolinos et al., 2008).