Effect of high-pressure treatment on the survival of Listeria monocytogenes Scott A in sliced vacuum-packaged Iberian and Serrano cured hams.
High-pressure treatment is useful for increasing the microbiological safety of ready-to-eat foods. With dry-cured hams, this treatment can be applied to the finished product after slicing and vacuum packaging. The effect of high-pressure treatment on the survival of inoculated Listeria monocytogenes Scott A and on the sensory characteristics of two Spanish dry-cured hams, Iberian and Serrano, was investigated. Ham slices were inoculated with L. monocytogenes at 6 x 10(6) CFU/g and held at 4 degrees C for 20 h before high-pressure treatment. During this holding period, the population of the pathogen declined by 0.44 and 0.51 log CFU/g in Iberian and Serrano hams, respectively. Treatment at 450 MPa for 10 min at 12 degrees C reduced L. monocytogenes populations by 1.50 and 1.16 log CFU/g in Iberian and Serrano hams, respectively. During the first week of storage at 4 or 8 degrees C, L. monocytogenes populations declined by an average 0.89 log CFU/g in pressurized Iberian ham and 2.09 log CFU/g in pressurized Serrano ham. After 60 days at 4 or 8 degrees C, the respective populations in pressurized and control hams were 3.24 and 4.70 log CFU/g for Iberian ham and 2.73 and 5.07 log CFU/g for Serrano ham. The color parameters L* and a* were not influenced by high-pressure treatment, and parameter b* was increased only in Iberian ham. Sensory characteristics of hams were not affected by high-pressure treatment. Treatment of Iberian and Serrano hams at 450 MPa for 10 min significantly reduced the population of L. monocytogenes Scott A without a detrimental effect on the sensory characteristics of the hams.
Morales
Pilar
P
Departamento de Tecnología de Alimentos, INIA, Carretera de La Coruña Km 7, Madrid 28040, Spain.
Calzada
Javier
J
Nuñez
Manuel
M
D000818:Animals; D015169:Colony Count, Microbial; D003257:Consumer Product Safety; D005511:Food Handling / Q000379:methods; D005516:Food Microbiology; D018857:Food Packaging / Q000379:methods*; D005519:Food Preservation / Q000379:methods*; D006801:Humans; D006874:Hydrostatic Pressure; D008089:Listeria monocytogenes / Q000254:growth & development*; D008461:Meat Products / Q000382:microbiology*; D013552:Swine; D013649:Taste; D013696:Temperature; D013997:Time Factors; D014618:Vacuum