Food Safety and Security

NON-TECHNICAL SUMMARY: Annually, human foodborne illness, as a consequence of the consumption of contaminated food, is estimated at 76 million cases with 5000 associated deaths. Currently, there is little information on the risk of salmonellosis and E. coli associated with the food supply, yet this type of data is important in assessing the safety of our nation\'s food supply. This initiative will address issues in determining the safety of our nation\'s food supply through risk analyses studies that will focus on Salmonella in poultry and E. coli in beef. These studies will develop as well as challenge current models for determining risk by evaluation of the microbiological, psychological, communication and epidemiological issues associated with risk. These studies will also incorporate the use of sensor technologies for rapid detection of food safety issues and their potential for reducing risk for the consumer. In further studies we will examine technologies for determining carcass contamination and host sources of Enterobacter sakazakii. <P>

APPROACH: <BR> Risk studies: <BR>1) Determine model robustness for predicting risk using current methods and minimal sample collection <BR>2) Analyze poultry at the farm, consumer and retail levels to determine dose response model changes <BR>3) Test value at risk models and real options to quantify food safety risks in monetary terms for industry and the public <BR>4) Evaluate intention and motivated behavior models of worker efforts toward food safety and consider facility culture. Investigate contributions of organizational, management, and operator levels to the risk model <BR>5) Test a series of communication best practices through case studies and sample messages for validation of the model <BR>6) Review foodborne Salmonella outbreaks, and examine epidemiological factors to compare with the risk model, determine the dose response relationship between Salmonella exposure via turkey consumption and development of infection <BR>7) Merge data from model challenge and report our findings. <BR><BR>Quality sensors: <BR>1) Determine the generation pattern, identification and quantification of volatile compounds by time using GC-MS<BR> 2)Validate profiles of indicator compounds from meat samples inoculated with Salmonella using microbiological, P-Module and GC-MS analysis<BR> 3)Develop prototype sensors that use thin film and nano-structure polymers for discriminating indicator compounds <BR>4) Determine the volatile organic compounds associated with E. coli by microbiological and GC-MS analysis; develop statistical correlation with the total numbers of E. coli <BR>5) Conduct preliminary evaluation of surface-enhanced Raman spectroscopic (SERS) techniques for discriminating indicator compounds. Evaluate gold colloids or golden nano-particles for capabilities to produce surface enhanced Raman signal. Evaluate porphyrin thin films for discriminating indicator compounds associated with meat compounds.<BR><BR> Microbial food safety:<BR> 1) Collect bovine rectal contents at slaughter to estimate E. coli O157:H7 and Salmonella prevalence. Determine antimicrobial susceptibility patterns of Salmonella<BR> 2) Test the effects of feeding probiotics on fecal shedding of E. coli O157:H7 by cattle <BR>3) Determine the retail prevalence of Salmonella and E. coli in beef to assess the risk to consumers. Compare the antimicrobial susceptibility of Salmonella isolates with pre-harvest data <BR>4) Search all diagnostic lab fecal samples (from food animals and pets) for Enterobacter sakazakii using selective and differential media to determine potential hosts and obtain an overall prevalence <BR>5) Sample carcasses for E. coli after hide removal, evisceration, trimming and chilling, and design a statistical sampling plan targeting the sites of highest contamination at each stage <BR>6) Examine a novel fluorescence imaging device and determine whether its use improves control of fecal contamination on carcasses <BR>7) Enhance graduate training, educational programs, and institutional collaborations.

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PROGRESS: 2005/06 TO 2008/05<BR>
OUTPUTS: The microbiologists assessed commercial and rapid kits to detect Salmonella in pre market and retail turkey. They studied Salmonella pathogenicitiy and antimicrobial resistance from process line birds. They identified a novel Salmonella strain with pathogenicity islands and was chosen for genome sequencing to provide insight into the relationship between poultry hosts and human disease. The agricultural economists developed VaR models to assist industry quantify food safety risks in monetary terms. Developed stochastic optimization models to assist policy makers evaluate the cost effectiveness of food safety measures PR/HACCP. Developed a framework to assess the human risk factor in turkey processing and to cost-effective risk mitigation strategies for intentional food contamination. Our epidemiologists have evaluated and developed tools for assessing the risk associated with turkey meat as a vehicle for Salmonella infections in humans using data from other states in the US. The pathogenic microbiologist assessed the public health risk of C. meleagridis in turkeys. Samples tested negative for C. meleagridis but positive for C. parvum which does not normally infect avian species, suggesting turkeys may be a vector. 227 samples from human cryptosporidiosis in MN were tested to determine the extent of C. meleagridis in humans and found no evidence that C. meleagridis poses a significant public health risk. Turkeys can be a source of human pathogenic Cryptosporidium species, but is unlikely to be significant. The agricultural engineers developed intelligent sensors for contamination detection in packaged beef using a portable automated system. They assessed volatile compounds of meat headspace during spoilage and Salmonella contamination using GC-MS. Parallel efforts to develop a metal-oxide array-based sensor was completed with maximum classification accuracies for Salmonella contamination of 79-87%. Work has also evaluated polymers and technologies for detecting components of meat headspace: Raman spectroscopy, SERS and metallo porphyrins. Studies are assessing indicator compounds of E. coli. Our communications experts evaluated individuals response to risk communication messages on food contamination or deliberate adulteration. Messages were tested to determine the degree of efficiency including comprehension, and promoting compliance. A survey of diverse publics, including general American macro-culture and underserved populations to explore impact of culture, learning styles, public outrage, and message source on message receptivity was carried out. The group worked with the NCFPD to address these objectives directly. Our psychologists demonstrated the intention model of food safety could be applied to food handlers and preparers in the home to protect against contamination. They showed dispositional disgust contributed to engaging in safe food practices. Optimistic bias was a fundamental process biasing judgments of what is safe food and who produces it. This has implications for interventions for reducing contamination in the home. Theoretical advances in motivating the avoidance of contamination and keeping food safe have resulted. <BR>PARTICIPANTS: Catherine M. Logue PI Margaret Khaitsa co PI John Mc Evoy co PI William Nganje co PI William Wilson co PI Suranjan Panigrahi co PI Clifford Hall co PI Verlin Hinsz co PI Gary Nickell co PI Robert Littlefield co PI Timothy Sellnow co PI Kimberley Beauchamp Julie S Sherwood Catherine Giddings Dawn Doetkott Chantal Nde Shana Petermann Aneesa Noormohamed Mohamed Fakhr Ernest S. Park Jared L. Ladbury Alice Scharnweber Dana M. Lawrence Mary Blume Kevin R. Betts <BR>TARGET AUDIENCES: Target audiences for this reseach include - other professional researchers, consumers and stakeholders, targets also include underrepresented groups and minorites where language may be an issue. These targets are met by distribution of the research through posters, papers and oral presentations at meetings using powerpoint where needed printed materials have been designed for specific audiences. Many of the projects and the research generated have been published in peer and non peer reviewed journals. <BR><BR>
IMPACT: 2005/06 TO 2008/05<BR>
Novel methods were developed for Salmonella detection in pre and post process turkey. A genome was sequenced to provide insight into animal pahtogens and human disease. Models have been developed to assess cost effective mitigation strategies in contamination. A novel tertiary PCR procedure was used to increase the sensitivity of Cryptosporidium detection in turkey fecal and cecal samples. This method allows for better downstream analysis of amplified targets to determine the species present. Novel sensors and materials have been developed for pathogen detection in meat and have applicaiton for other pahtogens. Our communication strategies have been remodeled leading to better understanding of risk messages. We have demonstrated how behaviour models can be used to imporve food safety and perception in the home and elsewhere. Data and information from all of these projects have been disseminated in a variety of manners inlcuding publications, oral and written presentaions to stakkeholders, consumers and professinal resarchers through attendence at professional meetings. Considerable amounts of the data and research have been published in a range of peer and non peer reviewed journals and popular magazines.