Overall objective of study: <BR>
To study the potential for production of microbiologically safe shellfish with extended shelf-life using the technology of high pressure processing.
Specific aims related to food safety: <BR>
To investigate the use of high pressure to inactivate selected pathogens (or surrogate pathogens) in shellfish. Microorganisms to be studied include various strains of non-pathogenic E. coli, Listeria spp, Vibrio spp. and selected viruses.
A surface response approach is being used to determine the treatment conditions (pressure, time and temperature) to achieve a 6-log inactivation of the selected microorganisms. Results to date indicate that the bacteria are more pressure resistant when present in the shellfish compared to seawater of buffer. L. innocua (representing Gram positive bacteria) was more pressure resistant than E. coli or Vibrio spp. For example, a treatment of ~500 MPa at 20oC for 2 min is sufficient to give a 6-log kill of E. coli in mussels, but only a 4-log kill of L. innocua. Preliminary results indicate that a bovine enterovirus virus, serotype 1 (VG5/27) could be inactivated by pressure. A treatment of 600 MPa for 5 min at 20oC gave at least 4 -log reduction in plaque forming units in mussels.