Survival and growth of Yersinia enterocolitica strains inoculated in skimmed milk treated with high hydrostatic pressure.
Four human pathogenic strains of Yersinia enterocolitica (serotypes O:1, O:3, O:8, and O:9) were inoculated (7-8 log CFU/ml) in UHT skimmed milk and treated at 300, 400, and 500 MPa for 10 min at 20 degrees C, and then kept at 8 degrees C to assess their evolution for 15 days. Treatments at 400 and 500 MPa caused the highest lethality, generally reaching counts below detection level (1 CFU/ml) in the culture media. At 300 MPa, the most baroresistant serotypes were O:3 and O:8. After 15 days of storage at 8 degrees C, Y. enterocolitica showed growth over 8 log (CFU/ml) in all treatments. Kinetic study of microbial inactivation in skimmed milk was performed with serotype O:8 at 300 MPa, showing a tailing after 35 min of pressure treatment.
De Lamo-Castellví
Sílvia
S
Centre Especial de Recerca Planta de Tecnologia dels Aliments, CeRTA, XiT, Departament de Ciència Animal i dels Aliments, Facultat de Veterinària Edifici V, Universitat Autònoma de Barcelona, Bellaterra 08193, Spain.
Roig-Sagués
Artur X
AX
Capellas
Marta
M
Hernández-Herrero
Manuela
M
Guamis
Buenaventura
B
D000818:Animals; D015169:Colony Count, Microbial; D003257:Consumer Product Safety; D005506:Food Contamination; D005516:Food Microbiology; D006801:Humans; D006874:Hydrostatic Pressure; D007700:Kinetics; D008892:Milk / Q000382:microbiology*; D012703:Serotyping; D013997:Time Factors; D015008:Yersinia enterocolitica / Q000145:classification / Q000254:growth & development*