HEAT DESTRUCTION OF SALMONELLA IN POULTRY FEED - EFFECT OF TIME, TEMPERATURE, AND MOISTURE

Salmonella enteriditis in poultry feed declines with increasing time o f exposure to heat. The interactions of temperature, time, and moistur e and their effect on the thermal death of S. enteriditis were establi shed in a factorial randomized experiment. Two other serotypes were te sted, and though there was some variation, the thermal death race foll owed the same basic pattern. A number of samples of poultry feed were collected and dried. After drying, the water was added back to give sp ecific percentages of moisture contents. The feed was then inoculated with salmonella and heated at. specific temperatures, with samples bei ng removed at certain time intervals. These samples were then cultured , and the surviving salmonella were counted. A linear relationship was obtained when the logarthm of survivors was plotted against the logar ithm of exposure time. These results permitted the construction of a g raph depicting that the rate of reduction in numbers of S. enteriditis when plotted against increasing temperatures is linear. This linear r elationship is apparent for other salmonella serotypes such as S. typh imurium and S. haardt. Our results show chat the thermal death rate of salmonella in poultry feed can now be predicted at varying time, temp erature, and moisture contents.