<OL> <LI> Expand mathematical models to predict the growth, survival and virulence of foodborne pathogens; <LI>validate current models in food; <LI> investigate variation in microbial growth and inactivation as affected by strain, lag phase duration, competitive flora, and package atmosphere; <LI>incorporate microbial models into a new version of the Pathogen Modeling Program (PMP), as well as other software programs, to assist in quantitative risk assessments.
Quantitative data on the effects of selected cultural parameters on the growth, survival,and virulence of foodborne pathogens will be collected in broth media and in representative foods, particularly meats, meat products, and poultry. Data will be appended into existing databases. Descriptive models will be developed from these results which will be incorporated into the existing Pathogen Modeling Program (PMP) and other risk assessment software. Software will be developed to permit linking a series of models that simulate a multi-step processing operation. Specific areas for research include understanding strain variation, lag phase duration, competitive flora, and the effects of different acidulants and humectants on model development.