2011 Annual Report
1a.Objectives (from AD-416)
1: Derive data and model Salmonella serotype changes in movement from incoming product, through whole bird processing, post-carcass cut-up, to final product.
1A. Develop an exposure assessment (EA) model for Salmonella serotype changes in movement from post-carcass cut-up to final product (cooked chicken parts).
2: Study the survival characteristics for Salmonella serotypes: are there serotypes that survive interventions on farm, in the processing plant and/or final product.
2A. Use the EA model to evaluate efficacy of a plastic chicken house floor for Salmonella serotype control.
3: Derive additional predictive microbiology data of multi-drug resistant (MDR) Salmonella spp., such as Salmonella Typhimurium DT104.
3A. Use MDR Salmonella serotypes to develop the predictive microbiology models needed for the EA model.
1b.Approach (from AD-416)
Predictive microbiology models for contamination, growth and survival of Salmonella serotypes on chicken parts will be developed and linked to form an exposure assessment model that predicts changes in incidence and number of Salmonella serotypes on chicken parts produced by different farm-to-table scenarios. The exposure assessment model will predict consumer exposure to Salmonella serotypes that survive cooking of chicken parts and that cross-contaminate cooked chicken parts during serving. The exposure assessment model will be designed to evaluate effects of interventions on consumer exposure to Salmonella serotypes of chicken origin. The intervention evaluated in the project will be a plastic chicken house floor that has potential to reduce Salmonella serotypes entering the processing plant and surviving on chicken parts after final processing.
Standard curves for determining the number of Salmonella on chicken parts were developed for serotypes Typhimurium and Kentucky. The standard curves are based on the mathematical relationship between the number of Salmonella on chicken parts and their time to detection in buffered peptone water during pre-enrichment. A study was initiated to determine the number of Salmonella on chicken parts and the number of Salmonella transferred from raw chicken to cooked chicken during meal preparation. Of 137 chicken parts examined thus far, 5 were found to contain Salmonella. One of the contaminated parts represented transfer of Salmonella from raw chicken to cooked chicken during meal preparation.
Risk analysis of Salmonella. Each year many Americans are sickened by Salmonella, a major foodborne pathogen frequently associated with poultry meat. To properly predict consumer exposure to Salmonella in food, an ARS researcher at Princess Anne, MD developed a modeling method to calculate the likelihood of Americans getting infected by Salmonella. The new modeling method has great potential to improve accuracy of current risk assessments conducted by regulatory agencies and that are used as the basis for policies and laws aimed at protecting the public from health hazards in the food supply.
Cold temperature is no problem for Salmonella. How does cold temperature affect Salmonella? An ARS researcher at Princess Anne, MD found that Salmonella can survive well and may even thrive when stored in cold conditions. A computer model was developed to forecast how Salmonella behaves in the cold (39 to 54F). The model was incorporated into the USDA, Pathogen Modeling Program (http://portal.arserrc.gov/) where it is being used by USDA and the chicken industry to predict the health risk from chicken stored under optimal and sub-optimal conditions of cold storage.
Oscar, T.P. 2011. Plenary lecture: innovative modeling approaches applicable to risk assessments. Food Microbiology. 28:777-781.