ABSTRACTStrains of the psychrotrophic bacteriaListeria monocytogenes, Aeromonas hydrophila and Yersinia enterocoliticawere inoculated onto samples of cooked mussel tissue and incubated at 5 and 10C under both aerobic and anaerobic conditions. These organisms were enumerated over a time course and data were analyzed to give values for the lag and generation times. All species grew under all conditions, and the rate of growth was similar under aerobic and anaerobic incubation. Predicted growth kinetic values from response surface models and measured growth rates forL. monocytogenes and A. hydrophilawere in reasonable agreement, but similar comparisons forY. enterocoliticagave shorter predicted lag and generation times than were measured. A combination of models from different sources would have given more accurate predictions than any one individual model.