Concerns about the safety of meat and other food products continue to exist, and, in some respects, have intensified and expanded to include, not only potential problems through natural and inadvertent, but also through potentially intentional, contamination with agents harmful to human health. Issues that increase concerns about food safety include: emergence of new and potentially more virulent pathogenic bacteria; development of resistance and cross-protection to various stresses by pathogens; increased at-risk for severe foodborne illness human populations; expanded food international trade; modified dietary, food preparation and food service preferences by consumers; and, limited food safety education of food handlers and consumers. In our efforts to address these issues and contribute to the safety of our food supply we need studies that will generate information useful to food safety risk assessors, policy makers and regulators, the food producing, processing and serving industries, public health authorities, and consumers. The knowledge generated will find application not only in food safety, but also in food security activities.
Thus, the objectives of the project are to: <OL> <LI> Develop knowledge that will allow improvements in live animal production, handling and transportation practices and decontamination processes or treatments at the pre-harvest, as well as the slaughtering stage, for control of bacterial pathogen contamination; <LI>Develop better procedures to examine the ecology of microbial pathogens in the environment and in meat products; <LI> Evaluate food formulations and processing methods, which may increase the risk of contamination of meat products with pathogens and identify formulations or processes (e.g., heating, drying, antimicrobials) to minimize such risks; <LI>Examine food distribution, handling and preparation for consumption practices that may affect pathogen survival, proliferation or inactivation and develop recommendations for providing safer products at the consumer level;<LI> Determine survival and growth kinetics of pathogens on raw and commercial ready-to-eat meat and poultry products of various types and formulations under various time-temperature conditions of storage (refrigeration, abusive temperatures) to identify those of high risk, and also, in so doing, generate data for risk assessments by industry, regulatory authorities and public health professionals; <LI> Determine whether decontamination treatments or processes, chemical preservatives and various pathogen control interventions and strategies applied to meats affect the microbial ecology and interactions between pathogenic bacteria and spoilage microorganisms; <LI> Evaluate the potential of decontamination treatments or processes, addition of chemical preservatives to formulations, food processing methods, and multiple preservation hurdles to influence survival, resistance and cross-protection of pathogens to subsequent food processing and preservation, or host-related stresses; <LI> Disseminate the data collected from the research studies to regulatory authorities, public health agencies, the meat industry, and consumers.
NON-TECHNICAL SUMMARY: The safety of meat products continuous to be a major issue of public concern in the United States and at the international level. The project will generate information useful to risk assessors, policy makers, regulators, food producers, processors, food service, public health authorities and consumers in their efforts to improve food safety, and may also find application in food security activities.
APPROACH: Exploratory studies will be conducted in broth and model systems (simple product formulations) to screen treatments and select factors that may enhance or compromise the safety and quality of meat products. For further evaluation of variables, studies will be carried out on meat products, either in the laboratory or in the field, and on a pilot or commercial scale. The results will be evaluated and the information generated will be used to design subsequent experiments. The procedures and methods to be used to conduct the experiments will depend on the objectives of each study and will be selected from officially approved methodologies, the literature, previously used methods from our laboratory or alternatively, procedures will be developed. Studies will be designed to generate information beneficial to regulatory authorities, public health agencies, risk assessors, animal producers, meat processors, and consumers by: (1) examining production practices and/or interventions (feeding practices, vaccines, probiotics, washing regiments) at the pre-slaughter stage to control or reduce the prevalence of pathogens (E. coli O157:H7 and Salmonella) on live animals and on resulting carcasses and other food products; (2) developing or improving on physical, chemical and biological decontamination treatments or processes to reduce contamination of carcasses during processing; (3) identifying food processing methods (e.g., curing, drying, marination, tenderization, restructuring) that increase the risk of contamination of meat products and develop formulations or processes that will control or minimize the risk; (4) estimating survival and growth kinetics of pathogens such as L. monocytogenes on commercial RTE meat and poultry products under various time-temperature storage conditions (refrigeration and abusive temperatures) to identify products of high risk that need further attention to ensure control of the pathogen (the information generated from these studies will also be useful in future risk assessment updates); (5) investigating alternative antimicrobial treatments or formulations (lactates, diacetates, organic acids, activated lactoferrin, nisin, and combinations of these) and/or post-packaging treatments for high risk RTE meat and poultry products; (6) determining whether decontamination treatments or processes and chemical preservatives have an impact on interactions between pathogens and the natural microbial flora; (7) identifying potential stress-adaptation or resistance by pathogens following exposure to factors such as food processing methods, decontamination treatments or processes, chemical preservatives, multiple preservation hurdles, sanitizers (acidic and alkaline), heat, cold, nutrient deprivation, low water activity, storage conditions and biofilm formation on equipment surfaces to subsequent food processing, preservation (e.g., acid, heat) and host-related (gastrointestinal fluid) stresses; and, (8) evaluating consumer practices that may lead to cross-contamination with pathogens in the home, and develop potential interventions (e.g., acid treatments) to reduce or inactivate potential pathogen contamination before consumption.
PROGRESS: 2004/07 TO 2007/12<BR>
OUTPUTS: Highly publicized foodborne disease outbreaks linked to consumption of contaminated meat and other food products have resulted in increased consumer concerns and interest in food safety. Regulatory and public health agencies, the meat industry and research institutions have set goals and objectives to reduce the incidence and eliminate or control pathogens at all stages of the food chain in order to limit outbreaks of illness and deaths as well as recalls of potentially contaminated products. This project has contributed to this effort through research, outreach and education activities. Work performed under this project has addressed and provided knowledge on the following: (i) pathogen sources and control strategies during animal production, handling and transportation to slaughter, (ii) pathogen reduction or control processes or interventions at the pre-harvest stage of beef slaughter (feeding practices, vaccines, probiotics, cattle hide washing), (iii) decontamination processes or treatments (physical, chemical, biological) during beef slaughter and fabrication (chemicals, chilling methods), (iv) improved procedures to examine the ecology of pathogens in the environment and in meat products, (v) food formulations and possessing methods which may increase the risk of contamination of non-intact meat products with pathogens (blade tenderization, moisture-enhancement), (vi) food formulations or processes to minimize such risks (antimicrobials, heating, drying), (vii) evaluation of risks of survival/growth kinetics of pathogens on raw and ready-to-eat meat and poultry products of various types and formulations under various time-temperature conditions of storage, (viii) generation of research data for risk assessments by industry, regulatory authorities and public health professionals, (ix) practices employed during distribution, processing, handling and preparation for consumption that may affect pathogen survival, proliferation or inactivation, (x) development of recommendations for providing safer products at the consumer level, (xi) whether various pathogen control interventions and strategies applied to meats affect the microbial ecology and interactions between pathogenic and spoilage bacteria, and (xii) the potential of various pathogen control interventions and strategies to influence survival, resistance and cross-protection of pathogens to subsequent food processing and preservation, or host-related stresses (heat, acid, simulated gastric fluid). The results and conclusions of experimental studies were disseminated, both nationally and internationally, through refereed journal publications (37), books (1), book chapters (11), conference proceedings, oral and poster presentations (65), final reports (12), bulletins and research reports (29), and invited presentations (26) to regulatory authorities, public health agencies, the meat industry, consumers, and research scientists. The generated information should be useful to these sectors in their efforts to optimize approaches, guidelines, recommendations and practices for application of raw product decontamination intervention strategies and processed meat preservation technologies. <BR> TARGET AUDIENCES: Audiences targeted were meat and other food producing, processing and serving industries, food safety risk assessors, policy makers and regulators, public health authorities, healthcare professionals and consumers.
IMPACT: 2004/07 TO 2007/12<BR>
The burden of foodborne illness in the United States is estimated at approximately 76 million illnesses, 325,000 hospitalizations, and 5,000 deaths each year. The foodborne pathogens, Salmonella and Escherichia coli O157:H7, are estimated to cause approximately 1.3 million and 62,000 cases of foodborne illness every year, respectively, while, annually, infections with Salmonella and Listeria monocytogenes result in 556 and 499 deaths, respectively. Food producing animals, contaminated water and the environment serve as sources of contamination of carcasses during the slaughtering process, and for resulting meat, poultry and other food products during production, processing, distribution, storage and handling. As it affects and may be fatal in young children, E. coli O157:H7 continues to be the pathogen of major concern for the beef industry because it is generally transmitted through consumption of non-intact products; mainly undercooked ground beef. Another pathogen of concern for the meat and poultry industry is L. monocytogenes which was responsible for major fatal outbreaks in recent years linked to contaminated ready-to-eat meat and poultry products. Furthermore, this pathogen has a fatality rate of 20-30 percent and causes serious clinical manifestations in susceptible population groups (the elderly, fetuses, neonates, and immunocompromised individuals). Thus, there is a need to control these and other pathogens at pre-harvest, during processing and preparation, as well as in meat plant environments and raw or ready-to-eat products. Application of antimicrobial interventions to live animals pre-harvest, carcasses during slaughter, and to processed products should be useful for reduction of contamination and control or inactivation of pathogens. In addition to improving product safety, application of such interventions assists meat processors to comply with required regulatory inspection criteria and industry specifications. It is important, however, that antimicrobial interventions are selected and applied based on results of research indicating conditions of application and achievement of objectives without development of unpredictable risks. The results of the studies completed and published under this project have provided knowledge that has found application in: the selection of pre-harvest pathogen control interventions (hide washing); decontamination of fresh beef (thermal pasteurization, chemical rinses); handling of raw products during storage, distribution and retail display; and alternatives (antimicrobials, heating treatments) for inactivating or inhibiting growth of pathogens on ready-to-eat products (beef jerky, frankfurters, luncheon meats, delicatessen products) during distribution, retailing and storage before consumption. The information generated from the studies will also be useful to food safety risk assessors, policy makers and regulators, the food producing, processing and serving industries, public health authorities, and consumers as they continue their efforts to improve the safety of our food supply. The knowledge generated will find application not only in food safety, but also in food defense activities.