Progress 09/15/06 to 09/14/10
Outputs
OUTPUTS: We investigated the use of GRAS lactic acid bacterial starter cultures (LABs) as pathogen surrogates in evaluating Critical Limits associated with heating/drying treatments used in producing ground and formed jerky products, and intervention treatments applied to beef carcasses to eliminate Escherichia coli O157:H7. We developed recommendations for use of a LAB pathogen surrogate, Saga 200 (Kerry Ingredients), as pathogen surrogate for in-plant validation of ground-and-formed beef jerky under commercial processing conditions and we have begun to work with plants to implement this validation protocol. Collected results are being, and will continue to be, compiled and shared to our web site: www.meathaccp.wisc.edu. We investigated the safety of ground-and-formed beef jerky prepared using home-style dehydrators and determined that consumers cannot achieve safety in the drying process; a 10-minute heating treatment in a preheated 275 degree F oven is recommended to ensure safety. These recommendations have been widely shared with consumers through a web-based fact sheet www.foodsafety.wisc.edu. As this project ended, a non-pathogenic E. coli strain from our collection, designated B-6 , and a commercial lactic acid bacteria starter culture (LHP-Dry; Chr. Hansen) showed promise as a pathogen-surrogates for validation of beef carcass interventions. The B-6 strain showed potential for use in plants employing hot water and/or warm organic acid (acetic or lactic acid) spraying treatments. The warm acid-spray treatments are commonly used in large-scale abattoirs. The LHP-Dry strain was found to be potentially useful for validating intervention treatments used at small-scale abattoirs, including ambient-temperature acid (acetic or lactic) spraying followed by a 1-day dry-aging period, hot-water spraying, or a 6 day dry-aging period. In-plant trials with both pathogen-surrogates were conducted to determine critical parameters for effectively applying two intervention treatments of potential usefulness in small-scale abattoirs. Specifically, we studied the amount of 5% acetic acid spray necessary per beef side to achieve targeted reductions of B-6 and LAB, and the spray-time per beef side with hot (135 - 150 degree F / 57.2 - 65.5 degree C) needed to achieve the targeted reductions. Work with both surrogates is continuing and we anticipate developing an in-plant protocol for intervention treatment validation, using these surrogates. Results of this work will be posted on our website http:://www.meathaccp.wisc.edu, and communicated to meat processors and regulators in workshop and one-on-one settings. PARTICIPANTS: Mr. R.J. Algino conducted the final phase of the beef-carcass intervention research. Mr. Algino is currently employed by JBS, the world's largest meat processing company, in Greeley, CO. Ms. Alena Borowski graduated with an M.S. degree in May 2009. She is currently the director of Quality Control for In-and-Out Burger in California. Dr. Gene Badtram assisted in the early phases of the beef-carcass intervention research. Dr. Badtram is a Meat Safety Veterinarian with the Wisconsin Department of Agriculture, Trade, and Consumer Protection - Division of Food Safety. Ten small-scale Wisconsin abattoirs assisted in the final phase of the beef-carcass intervention treatment research. TARGET AUDIENCES: Small meat processors and state and federal regulators. PROJECT MODIFICATIONS: We found that the hardiest lactic acid bacteria culture tested (LHP-Dry) was not suitable as a pathogen-surrogate across all conditions encountered in the range of beef-carcass intervention treatments for small-scale and large-scale abattoirs. A non-pathogenic E. coli strain from our collection, referred to as B-6, does appear to have promise as a pathogen-surrogate under conditions in which LHP-Dry was not suitable, so our final work included this bacterium as a potential pathogen-surrogate.
Impacts
Two commercial lactic acid starter cultures, LABs, were evaluated as potential pathogen surrogates in the manufacture of ground-and-formed beef jerky. Ground-and-formed beef jerky was prepared using 12 commercial smokehouse schedules or using home-style dehydrators. Pathogen inoculum or an LAB was added to ground beef seasoned with 1 of 3 spice mixtures. Product was dried and change in inoculum concentration determined. Saga 200 was determined to be an effective pathogen surrogate for in-plant validation of the manufacture of ground-and-formed beef jerky. When using home-style dehyrators, we determined that consumers can only achieve the recommended 5-log pathogen reduction using home-style dehydrators if drying is followed by heating for 10-minute in a 275 degree F oven. To identify organisms that might serve as surrogates for Escherichia coli O157:H7 in validating beef-carcass intervention treatments, we first selected pathogen strains to serve as a basis for comparison. 23 genetically diverse strains of E. coli O157:H7 were screened for resistance to heat, acid, and cold. Similar trials were conducted with 7 LAB starter cultures which were considered potential pathogen-surrogates. The hardiest E. coli O157:H7 strains (12 total) and LAB strain (LHP-Dry), along with 5 strains each of Biotype I E. coli and non-E. coli coliform bacteria, were used in trials which compared the survival of E. coli O157:H7 against potential pathogen-surrogates on beef pieces using small-plant interventions: 6-day dry-aging, or hot-water spraying, or ambient-temperature acid-spraying followed by 1-day dry-aging, or interventions used in large-scale abattoirs: hot water spraying followed by warm-temperature acid spraying. E. coli O157:H7 and surrogates survived better on adipose tissue than on lean tissue. Under dry-aging and in trials with acid-spraying followed by 1-day dry-aging, LHP-Dry, Biotype I E. coli and coliforms all survived at least as well as E. coli O157:H7. In hot-water treatment, LHP-Dry survived at least as well as E. coli O157:H7, when hot-water treatment was followed by acid-spraying, and in trials with warm acid-spraying, only Biotype I E. coli survived at least as well as E. coli O157:H7. From the Biotype I E. coli strains, one strain, B-6, was the most acid-tolerant and heat-tolerant of the Biotype I E. coli strains tested, and survived at least as well as E. coli O157:H7 in trials with acetic acid-spraying followed by 1-day dry-aging, spraying of warm 5% acetic acid, and hot-water spraying followed by warm-acid spraying. As previously noted, a single organism is unlikely to be a suitable pathogen-surrogate across all beef-carcass intervention treatments, so we concluded by using both LHP-Dry and B-6 to evaluate efficacy and determine critical parameters for use of hot-water spraying or ambient-temperature spraying of 5% acetic acids in small-scale abattoirs. The results of our work will provide meat researchers and processors two pathogen-surrogates for use during in-plant evaluation of beef-carcass intervention treatments. In-plant evaluation will be necessary to meet regulatory and consumer expectations for meat safety.
Publications
- Ingham, S., R. Algino, B. Ingham, and R. Schell. 2010. Identification of Escherichia coli O157:H7 surrogate organisms to evaluate beef carcass intervention treatment efficacy. J. Food Prot. 73:1864-1874.
|
Progress 09/15/08 to 09/14/09
Outputs
OUTPUTS: Web-based materials are being developed to help train processors on the use of lactic-acid bacterial starter cultures in process validation in the production of ground-and-formed beef jerky and in the validation of beef carcass intervention treatments (organic acid washes and/or water washes). All project materials will be shared here: www.meathaccp.wisc.edu Regional in-plant training programs for meat processors and state inspectors are being planned. PARTICIPANTS: Staff for this project included two graduate students: Alena Borowski, M.S. University of Wisconsin-Madison, May 2009; and Ryan Algino, Ph.D. candidate. Both graduate students have been supported by undergraduates hourly workers. Faculty contributing to this project include Dr. Barbara Ingham, Food Science Extension Professor, University of Wisconsin-Madison. TARGET AUDIENCES: Target audience for this project is small and very small meat processors who slaughter beef and/or process beef jerky. PROJECT MODIFICATIONS: Nothing significant to report during this reporting period.
Impacts
The United States Department of Agriculture (USDA) requires scientifically validated intervention treatment(s) for beef slaughter and critical limits used in the manufacture of beef jerky. Small-scale abattoirs and jerky manufacturers lack the resources to perform validation studies and the USDA prohibits use of pathogens in plants to evaluate the effectiveness of interventions. We evaluated the use of non-pathogenic surrogate organisms to validate carcass intervention treatments used at slaughter and critical limits used in the manufacture of ground-and-formed beef jerky. Commercial lactic acid bacteria (LAB) starter cultures were evaluated for cold-, acid- and heat-tolerance; one, Bactoferm LHP Dry (Pediococcus acidilactici and Pediococcus pentosaceous) was selected for evaluation as a surrogate for Escherichia coli O157:H7 in small beef abattoirs, and two others, Saga 200 (Pediococcus spp.) and Biosource (Pediococcus acidilactici), were consistently more heat-resistant than Salmonella and E. coli O157:H7 and were evaluated as pathogen surrogates in the manufacture of ground-and-formed beef jerky. We also evaluated the effectiveness of Biotype I and other non-E. coli coliforms as surrogates in the validation of beef carcass interventions. To evaluate the effectiveness of beef slaughter interventions, beef brisket (adipose and lean) and cod membrane were subjected to 6-day dry-aging or exposed to organic acids (2.5 percent acetic acid, 2 percent lactic acid, or Fresh Bloom) plus 1-day dry-aging in a model abattoir cooler. Survival of LAB Bactoferm LHP Dry was not significantly different from E. coli O157:H7 in simulated interventions used by small abattoirs. We are continuing to evaluate a Biotype I E. coli and other LABs in intervention treatments using a wider array of acid treatments. To evaluate the effectiveness of LAB as pathogen surrogates in beef jerky manufacturing, LAB- and pathogen-inoculated ground-and-formed beef jerky was processed using six processes, differing widely in lethality, using a commercial smokehouse. Both LAB cultures, Saga 200 and Biosource, consistently predicted adequate process lethality; defined as greater than a 5.0 log CFU reduction of either pathogen. When either LAB decreased more than 5.0 log CFU, processes were sufficiently lethal against Salmonella and E. coli O157:H7 in 100 percent of samples (n = 39, 40). Use of LABs as pathogen surrogates for ground-and-formed beef jerky process validation was field-tested by three small meat processors. Processors found this technique easy to use for process validation. Additional research investigated the use of LABs as pathogen surrogates in ground-and-formed beef jerky processed in home-style dehydrators. This research showed that methods commonly recommended to consumers for drying beef jerky in home-style products do not produce a safe product. Recommendations are being prepared to share with consumers wishing to make ground-and-formed beef jerky at home.
Publications
- Borowski, A., S. Ingham and B. Ingham. 2009. Lethality of home-style dehydrator processes against Escherichia coli O157:H7 and Salmonella serovars in the manufacture of ground-and-formed beef jerky and the potential for using a pathogen surrogate in process validation. J. Food Protection 72:1234-1247. Borowski, A., S. Ingham, and B. Ingham. 2009. Validation of ground-and-formed beef jerky processes using commercial lactic acid bacteria starter cultures as pathogen surrogates. J. Food Protection 72:(in press)
|
Progress 09/15/06 to 09/14/07
Outputs
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.
TARGET AUDIENCES: Meat Processors
Impacts
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.
Publications
- No publications reported this period
|