INFLUENCE OF TEMPERATURE, PH, SODIUM-CHLORIDE AND SODIUM-NITRITE ON THE GROWTH OF CLINICAL AND FOOD MOTILE AEROMONAS SPP STRAINS

Effects of temperature (4, 10, 28, 37 and 45 degrees C), pH (3.5, 4.5, 6.0, 7.0 and 8.5), sodium chloride content (% NaCl, w/v) (0.5, 2.5, 4 .5 and 6.5 %) and sodium nitrite concentration (mu gml(-1) NaNO2) (0, 62, 125, 250, 500 and 1000 mu gml(-1)) on the growth of six clinical a nd six food motile Aeromonas spp. strains were determined. All food st rains and two of clinical origin grew when the temperature of incubati on was 4 degrees C. At pH 4.5, only two food strains grew. At 4.5 % Na Cl, three clinical and three food strains grew, but they did not reach ed a population of 1 x 10(9) CFUml(-1) NaNO2 concentration, only A. hy drophila reached population of 1 x 10(9) CFUml(-1). In relation to the parameters studied, no remarkable differences between the behaviour o f clinical and food strains were observed. These data suggest that sev eral motile Aeromonas spp. strains are capable of growing and to reach hazardous population densities at conditions currently considered ade quate for preventing the growth of foodborne pathogens in foods.