THE STUDY OF SALMONELLA-ENTERITIDIS GROWTH-KINETICS USING RAPID AUTOMATED BACTERIAL IMPEDANCE TECHNIQUE

In order to study strain-specific differences in their growth behaviou r at different, and particularly lower, temperatures, generation times for 45 strains of Salmonella enteritidis isolated from food were dete rmined impedimetrically over a temperature range from 7 to 42 degrees C. In practical terms, 7 degrees C is the minimum requirement for Salm . enteritidis growth, and generation time variability increases marked ly as this temperature is reached. Reports in the literature describin g psychrotrophic behaviour and multiplication at lower temperatures ca nnot be confirmed. Generation time variability increased as temperatur e moved away from the optimal range with variation coefficients tendin g to rise as temperature fell. The great variability of multiplication parameters near the growth limit found in Salm. enteritidis may also be a characteristic of other bacterial species. It is therefore impera tive to commence studies on larger numbers of strains to allow predict ion of their behaviour at lower temperatures.