Start Date: May 27, 2010
End Date: Jan 19, 2011
An exposure assessment (EA) model that predicts the change in incidence and number of Salmonella serotypes on chicken during movement from post-carcass cut-up to final product (cooked chicken) will be developed in an Excel spreadsheet and simulated using @Risk, a spreadsheet add-in program. The EA model will simulate two exposure pathways: 1) consumer exposure to Salmonella serotypes that survive cooking; and 2) consumer exposure to Salmonella serotypes that spread to lettuce. The exposure pathways will be modeled as a series of linked unit operations (cold storage, meal preparation, cooking) and associated pathogen events (contamination, growth or survival). Whole chicken parts will be incubated in laboratory broth and the incidence and number of Salmonella serotypes on the parts will be determined as a function of polymerase chain reaction (PCR) detection time. Kinetic data for growth and survival of Salmonella serotypes on chicken meat (skin, breast and thigh) and lettuce with native microflora will be collected in challenge trials with low and ecological doses of serotypes resistant to multiple antibiotics (MDR). These data will be used to develop and validate General Regression Neural Network and Monte Carlo Simulation (GRNN-MCS) models for growth and survival of Salmonella serotypes on chicken meat and lettuce during temperature abuse, cold storage, cooking and cooling. Outputs of the GRNN-MCS models will be probability distributions for log change of Salmonella serotype numbers that will be directly linked to individual unit operations and pathogen events in the EA model. The EA model will also be designed to evaluate efficacy of interventions on consumer exposure to Salmonella serotypes on chicken produced by different farm-to-table scenarios. Data will be acquired and used in the EA model to evaluate efficacy of three interventions for Salmonella control: a) a new chicken house design (AviHome); b) high hydrostatic pressure processing of chicken in the processing plant; and c) home application of an Italian marinade.