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Our first objective is to investigate the use of GRAS lactic acid bacterial starter cultures (LABs) as pathogen surrogates in evaluating Critical Limits associated with a) heating/drying treatments used in producing ground & formed jerky products, and b) intervention treatments applied to beef carcasses and edible offal to eliminate Escherichia coli O157:H7. We have conducted preliminary studies with LABs as pathogen surrogates in the production of whole muscle beef jerky and have had promising results. The meat inspection division of the Wisconsin Department of Agriculture, Trade and Consumer Protection (meat safety inspection division) will be a key collaborator in these research efforts. <P>
Our second objective is to undertake comprehensive efforts to teach processors how to perform in-plant validation using LABs. We will develop a web-accessible database of in-plant validation study results and develop model training programs for use nationwide that teach processors and meat inspectors how to utilize the results of individual in-plant validation trials. Our outreach efforts will be critically evaluated before being shared nationally. We will collaborate with state inspection programs and food safety specialists in South Carolina, Kansas and Pennsylvania on these efforts.
NON-TECHNICAL SUMMARY: Nearly 7,300 small and very small meat and poultry plants play an important role in the meat industry in the United States. Under the mandated Hazard Analysis Critical Control Point (HACCP) system, small and very small plant operators are being asked to scientifically validate Critical Limits used in their HACCP plans to control pathogenic bacteria such as Escherichia coli O157:H7. For most Critical Limits, little government guidance is available for validation and the onus of validation is on the processor. There is currently little validation information available for Critical Limits associated with two very important beef processing situations: heating/drying regimes used in making ground & formed beef jerky and beef carcass intervention treatments. This project will assist small and very small plants in HACCP validation through: 1) development of methods for in-plant validation of heating/drying regimes used in making ground and formed beef jerky and for in-plant validation of beef carcass interventions, using lactic acid bacteria as pathogen surrogates; and 2) development of a multi-media outreach program to disseminate project results and assist processors and regulators in validating Critical Limits. Preliminary research in our laboratory has demonstrated the likelihood of success for this approach.
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APPROACH: We intend to compare survival of Salmonella serovars, E. coli O157:H7, and several commercial LAB cultures, during heating/drying processes on ground and formed beef jerky having a wide range of lethality. A jerky batter will be prepared using pilot-plant scale equipment in our laboratory and a standardized formulation. Portions of the batter will be inoculated with high levels of either a multi-strain cocktail of E. coli O157:H7, a multi-strain cocktail of Salmonella serovars, or the LAB culture being tested. Jerky strips will be extruded, cut to standard dimensions, and placed on screens which will then be processed. Inoculum numbers will be determined immediately before processing, at an intermediate time during processing, and at the end of the process using standard laboratory methods. A full factorial experimental design will be used with 1 jerky formulation x 3 processing treatments (high-, intermediate-, and low-lethality) x 2 replicates per trial x 3 types of inoculum (E. coli O157:H7, Salmonella serovars, or LAB) x 3 sampling times x 3 trials. Laboratory results (identification of appropriate LAB culture for validation, inoculum level, inoculation and sampling method, interpretation of results) will be used to design an in-plant protocol for process validation of heating/drying of ground and formed jerky. Beef carcass intervention treatments (acid-spray and dry-aging) will be established based on in-plant conditions based on real-world situations (data gathered as part of this grant.). Simulated treatments will involve inoculating a multi-strain cocktail of E. coli O157:H7 and variety of commercially available GRAS LABs onto inoculated on beef lean (brisket cut surface), beef fat (brisket ventral surface), and beef fascia (flank), as well as each type of edible offal (tongue, heart, liver). Following intervention (dry again or organic acid wash) microbial numbers will be enumerated using standard laboratory methods. A full factorial experimental design will be used with 5 beef parts or edible offal x 3 treatments (median and both extremes) x 2 replicates per trial x 2 types of inoculum (pathogen or LAB) x 2 or 4 sampling times x 3 trials for each type of acid spray and dry-aging. Laboratory results (identification of appropriate LAB culture for validation, inoculum level, inoculation and sampling method, interpretation of results) will be used to design an in-plant protocol for process validation of carcass interventions in small and very small beef slaughter operations.
<P>PROGRESS: 2007/09 TO 2008/09<BR>
OUTPUTS: Work on the use of GRAS lactic acid bacterial starter cultures as pathogen surrogates in validating jerky process lethality has proceeded well. The project methods and outputs were presented at the 2008 Annual Convention of the Wisconsin Association of Meat Processors. The method for jerky process lethality validation was described and demonstrated at the 2008 Jerky Manufacturing Workshop in Madison, WI. The method has been field tested in commercial processing plants on six occasions and was found to be easy to use. We have also made good progress in evaluating the use of GRAS lactic acid bacterial starter cultures as pathogen surrogates in validating beef carcass intervention treatments. Model system trials simulating interventions used in small-volume abattoirs have been completed. Trials simulating large-volume abattoir interventions are ongoing. The potential for this validation technique was described at the 2008 Annual Convention of the Wisconsin Association of Meat Processors and has been field tested at approximately 10 small-volume abattoirs and 3 large-volume abattoirs. <BR> PARTICIPANTS: The project is co-directed by Barbara and Steve Ingham. Graduate students working on the project are Ryan Algino and Alena Borowski. Dr. Gene Badtram of the Wisconsin Department of Agriculture, Trade & Consumer Protection's Meat Safety & Inspection Bureau has assisted in field-testing. Dr. John Ruby of Smithfield Beef has also assisted in field-testing. <BR> TARGET AUDIENCES: Our target audience members are small-scale meat processors in Wisconsin and nationwide. We are currently in the research phase of the project. The extension phase of the project will begin full-strength in 2009. <BR> <BR>
IMPACT: 2007/09 TO 2008/09<BR>
Jerky processors in Wisconsin have been able to evaluate their process for lethality against Salmonella and Escherichia coli O157:H7 by serving as field-testing venues for our validation method.
<BR> <BR> PROGRESS: 2006/09/15 TO 2007/09/14<BR>
OUTPUTS: Part 1. Beef carcass intervention treatments Task1.1: Determine range of conditions occurring during carcass interventions at beef slaughter plants. Status1.1: Work completed; paper published in J. Food Science; poster presented at IFT meeting. Task1.2: Simulate intervention conditions at Biotron or in lab; determine comparative survival of E. coli O157:H7 and LABs during simulated interventions Status1.2: Model system for simulating dry-aging has been developed (beef brisket, edible offal, cod membrane pieces in small chambers housed in Biotron room). Studies to simulate dry-aging are nearing completion. Comparison done between sponge-sampling (used by processors and regulators) and excision-sampling (often used by researchers) Task1.3: Analyze data; determine what reduction in numbers of specific LABs provides adequate assurance that intervention is effective against E. coli O157:H7 Status1.3: Initial data analysis for dry-aged beef has been conducted Task1.4: Develop protocol for processors to use when doing in-plant validation Status1.4: Prototype has been developed. Task1.5: Pilot materials for teaching processors to use the protocol. Status1.5: no work on this task Task1.6: Present materials for teaching processors to use the protocol. Status1.6: no work Task1.7: Summative evaluation of how materials are used by processors. Status1.7: no work Part 2. Ground & Formed Beef Jerky Task 2.1: Develop jerky-making, inoculation, and thermal-processing protocols. Status 2.1: Work is on-going. Task 2.2: Compare survival of E. coli O157:H7, Salmonella serovars, and LABs during thermal processing of ground & formed beef jerky Status 2.2: Work is on-going. Task 2.3: Analyze data; determine what reduction in numbers of specific LABs provides adequate assurance that intervention is effective against E. coli O157:H7 and Salmonella serovars. Status 2.3: no work. Task 2.4: Develop protocol for processors to use when doing in-plant validation Status 2.4: no work. Task 2.5: Pilot materials for teaching processors to use the protocol. Status 2.5: no work. Task 2.6: Present materials for teaching processors to use the protocol. Status 2.6: no work. Task 2.7: Summative evaluation of how materials are used by processors. Status 2.7: no work. <BR> TARGET AUDIENCES: Meat Processors
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IMPACT: 2006/09/15 TO 2007/09/14<BR>
Simple, effective methods using lactic acid bacteria will be developed which will allow small and very small meat processors to validate beef carcass interventions in use in their own plant; and jerky makers will be able to validate heating/drying regimes that they use in making a ground and formed product.