Role of quantity and quality of fat in meat models inoculated with Listeria innocua or Salmonella Typhimurium treated by high pressure and refrigerated stored

Several variables can influence the effects of high hydrostatic pressure processing (HPP), but the role of fat in the treated sample is still uncertain. We designed a model by which controlling the known variables we could elucidate that role. We applied 400 MPa for 2 min to minced chicken samples inoculated with Listeria innocua and Salmonella Typhimurium mixed with 10% and 20% of three fat types with different fatty acid composition. Microbial counts were performed during 60 days of refrigerated storage either at 2 °C or 8 °C. Immediately after HPP bacterial growth was independent of the type and percentage of fat content, but a possible effect of type of fat could be observed after 60 days of cold storage. © 2009 Elsevier Ltd. All rights reserved.