An official website of the United States government.
<ol> <li>Determine the variation between strains of a pathogen,
<li>Create models for the lag phase duration when environmental conditions change,
<li>Model growth and survival in modified atmosphere packaged foods, and
<li>Incorporate microbial models into a new version of the Pathogen Modeling Program (PMP) which can model a processing operation and conduct risk assessments.</ol>
Quantitative data will be collected on the growth and survival of E. coli 0157:H7, Salmonella, Listeria monocytogenes, and Shigella flexneri in broths and representative foods (particularly meats and meat products) under conditions of MAP and changing environments. Emphasis will be on the durations of the lag phase, growth rates and rates of death during storage. MAP will include CO2 and low 02 atmospheres. Additional factors will be incorporated into existing models (acid anions, other humectants besides NaCl). Descriptive models will be developed from these results which will be incorporated into the existing PMP. The PMP will be further developed to permit linking a series of models that simulate a multi-step processing operation and by using Monte Carlo techniques to estimate the likely distribution of pathogens in the product and probability of illness from consuming a particular food.