Progress 07/01/05 to 06/30/10
Outputs
OUTPUTS: Meat samples were spray washed with water (control), 2% lactic acid, 2% acetic acid, or 2% levulinic acid at 130F. After drying, the meat samples were inoculated with pathogenic bacteria and vacuum packaged. The experiment was replicated in four model systems including: Esherichia coli O157:H7 inoculated onto pieces of beef carcass tissue; Salmonella spp. inoculated onto pork carcass tissue; Salmonella spp. inoculated onto chicken carcass tissue, and; Listeria monocytogenes inoculated onto slices of ready-to-eat turkey roll. Turkey slices were stored at 4 deg. C and L. monocytogenes counts determined at 0, 2, 4, 8, 12, and 16 weeks. All other samples were stored at 8 deg. C and pathogen counts determined at 0, 2, 4, 6, and 8 weeks. In the decontamination studies, acid washes lowered recoverable numbers of pathogens by only 0.6 to 1 log/sq cm as compared to controls that did not receive any wash treatment, and only lactic acid lowered the number of pathogens recovered as compared to the water wash. Washing with levulinic acid at higher temperatures (68.3 or 76.7 deg. C) did not result in additional decontamination of Escherichia coli O157:H7 from beef plate. Only acetic acid prevented growth of E. coli O157:H7 on beef plate and Listeria monocytogenes on turkey roll, and this treatment also imparted a residual effect that reduced numbers of Salmonella on chicken skin to below recoverable levels. In conclusion, washing with levulinic acid displayed no advantages for reducing pathogens on meat surfaces as compared to the current industry standards of lactic and acetic acids. Only lactic acid washes added small decontaminating capacity as compared to water, and only acetic acid displayed residual activity to prevent growth of pathogens. This highlights the need for the meat industry to reconsider the effectiveness of organic acid washes relative to their combined ability to decontaminate meat tissues and subsequently inhibit growth of pathogens, and especially the extent to which washing with organic acids contributes to a total food safety program. PARTICIPANTS: American Meat Institute Foundation TARGET AUDIENCES: The food industry is the primary target audience, especially those industry segments dealing with processed meats and other ready-to-eat products including seafood and fresh produce. Information will be disseminated to those audiences via publication of results in relevant peer reviewed journals and by presentations at affiliated scientific and industry venues. PROJECT MODIFICATIONS: Not relevant to this project.
Impacts
Knowledge gained from these studies has direct application for controlling important food-borne pathogens thereby leading to a safer food supply. Food poisoning costs the United States $152 billion dollars annually, $505 for every American. Food safety is the highest rated non-economic issue for United States consumers, and they indicate a willingness to pay up to 30 percent more for products with a safety certification label. That translates into an economic impact of over $170 billion based on yearly supermarket food sales alone.
Publications
- Carpenter, C. E., Smith, J. V., & Broadbent, J. R. 2011. Efficacy of washing meat surfaces with 2% levulinic, acetic, or lactic acid for pathogen decontamination and residual growth inhibition: Meat Science, 88: 256-260.
- Carpenter, C. E., Smith, J. V., & Broadbent, J. R. 2011. Efficacy of washing meat surfaces with 2% levulinic, acetic, or lactic acid for pathogen decontamination and residual growth inhibition: Meat Science, 88: 256-260.
|
Progress 01/01/09 to 12/31/09
Outputs
OUTPUTS: Meat samples were inoculated with 5-6 log CFU/sq cm of multi-strain cocktails of pathogenic bacteria. After inoculation, samples were sprayed with water (control), 2% lactic acid, 2% acetic acid, or 2% levulinic acid at 130F to replicate concentration and temperature used for carcass spray in the industry. Some inoculated samples were not washed, and these served as a no-intervention control. Samples were vacuum packaged and stored overnight at 4 deg. C. Residual counts of pathogenic bacteria on each sample were made, and extent of decontamination calculated as the log reduction in CFU in treated samples compared to the no-intervention control and to the water wash. The experiment was replicated in four model systems including: Esherichia coli O157:H7 inoculated onto pieces of beef carcass tissue; Salmonella spp. inoculated onto pork carcass tissue; Salmonella spp. inoculated onto chicken carcass tissue, and; Listeria monocytogenes inoculated onto slices of ready-to-eat turkey roll. Water and acid washes did not result in significant decontamination of L. monocytogenes on turkey slices or E. coli O157:H7 on beef plate as compared to the no-wash controls. Acid washes resulted in about 1 log decontamination of Salmonella on pork and chicken skin as compared to the no-wash controls, although acid washes were generally no more effective for decontamination than water washes. We also washed beef tissue inoculated with of E. coli O157:H7 using levulinic acid at various concentrations (0, 0.5, 1.0, and 2.0%) and temperatures (130, 155, and 170F). The treatments were not effective for decontamination of E. coli O157:H7 on beef surface except for a 1.3 log decontamination using 2% levulinic acid at 76.7C. In summary, washing with organic acids treatments was generally not effective at reducing numbers of pathogenic bacteria regardless of organic acid, bacterial species, or meat tissue type. PARTICIPANTS: American Meat Institute Foundation TARGET AUDIENCES: The food industry is the primary target audience, especially those industry segments dealing with processed meats and other ready-to-eat products including seafood and fresh produce. Information will be disseminated to those audiences via publication of results in relevant peer reviewed journals and by presentations at affiliated scientific and industry venues. PROJECT MODIFICATIONS: Nothing significant to report during this reporting period.
Impacts
The meat industry has widely adopted the use of organic acid washes based on research that reports 2-3 log reduction in bacterial numbers. In contrast, our results are consistent with other research indicating that organic acids are not effective for decontamination of meat tissues. This highlights the need for the meat industry to reconsider the effectiveness of organic acid washes for decontamination of meat tissues, especially the extent to which washing with organic acids contributes to a total food safety program.
Publications
- Walsh, M. K. and Carpenter, C.E. 2009. Textured whey protein product, US Patent No. 7,597,921.
- Allen, K. E., Carpenter,C. E., Walsh, M. K. 2007. Influence of protein level and starch type on extrusion-expanded whey product. Int. J. Food Sci. Tech. 42:953-960.
- Carpenter, C.E., Broadbent, J.B. 2006. Method of inhibiting growth of Listeria monocytogenes using levulinate. Patent filed August 2007 .
- Taylor, D.P., Carpenter, C. E. and Walsh. M. K 2006. Influence of sulfonation on the properties of expanded extrudates containing 32% whey protein. J. Food Sci. 71 :Nr 2, E17-24.
- John, L., Cornforth, D. P., Carpenter, C. E., Sorheim, O., Pettee, B. and Whittier, D. 2005. Color and thiobarbituric acid values of cooked top sirloin steaks packaged in modified atmoshperes of 80% oxygen, or 0.4% corbon monoxide, or vacuum. Meat Sci. 69:441-449.
|
Progress 01/01/08 to 12/31/08
Outputs
OUTPUTS: We worked with CHAD company (St. Louis, MO) to design and build a spray apparatus for the work outlined in Objective 4. After receipt of the spray apparatus, we completed protocol development and optimization for Objective 4 using non-pathogenic Listeria innocua. Protocols were validated including use of the washing apparatus, inoculation and storage of samples, recovery of bacteria, and standard operating procedures to ensure containment of the pathogens. Approval to implement the studies with pathogens was granted by our institutional biosafety committee in March 2008. We procured the E. coli strains from Dr. Steve Ingham of the University of Wisconsin-Madison, and the Salmonella strains from Dr. Vijay Juneja of the USDA Agricultural Research Service. Most of the studies outlined for Objective 4 have been initiated with scheduled completion during 2009. PARTICIPANTS: American Meat Institute Foundation TARGET AUDIENCES: The food industry is the primary target audience, especially those industry segments dealing with processed meats and other ready-to-eat products including seafood and fresh produce. Information will be disseminated to those audiences via publication of results in relevant peer reviewed journals and by presentations at affiliated scientific and industry venues. PROJECT MODIFICATIONS: Nothing significant to report during this reporting period.
Impacts
The planned research will validate the use of levulinic acids as an alternative to the lactic and acetic acids currently in use for topical decontamination of pathogenic bacteria on surfaces of fresh and ready-to-eat meats. Levulinic acid is expected to provide surface decontamination similar to lactic and acetic acids when applied at concentration (2%) and temperature (130 degrees F) that predominate in the industry. However, owing to the greater boiling point of levulinic acid, it may be viable to apply levulinic acid at temperatures greater than 130 degrees F. This could have several positive implications for food safety and cost effectiveness including greater decontamination of pathogens, use of lower acid concentrations, and lessened problems with acid vapors that corrode equipment and facilities. Levulinic acid is also expected to provide greater residual protection against pathogens than lactic and acetic acids, and may find use in combination or in rotation with other topical decontaminants to guard against emergence of acid-resistant strains.
Publications
- Thompson, R.L., Broadbent, J.R., Carpenter, C.E., Martini, S. 2008. Control of Listeria monocytogenes in ready-to-eat meats containing sodium levulinate, sodium lactate, or a combination of sodium lactate and sodium diacetate. J. Food Sci. 73:M239-244.
- Walsh, M.K., Nam S.-H., Pette, B.C., Carpenter, C.E. 2008. Characterization of textured whey protein produced at varying protein concentrations. J. Food Processing Preservation 32:503-516.
- Walsh, M.K. and Carpenter, C.E. 2008. Whey protein-based meat analogs . Whey Processing, Functionality and Health Benefits Chapter 8:185-200.
- Thompson, R.L. 2007. Control of Listeria monocytogenes in ready-to-eat meats containing levulinate, lactate, or lactate and diacetate. MS thesis, Utah State University, Logan, UT.
|
Progress 01/01/07 to 12/31/07
Outputs
Bologna was formulated to contain sodium levulinate (1%, 2%, or 3% v/wt), sodium lactate (2%), a combination of sodium lactate and diacetate (1.875% lactate, 0.125% diacetate), or no antimicrobial. Slices of bologna were inoculated with 10E2 to 10E3 CFU/cm2 of a 5-strain cocktail of L. monocytogenes, vacuum packaged, and stored at 2 degrees C for 0-12 weeks. Bacterial counts reached over 10E7 CFU/cm2 on no-additive bologna after 12 weeks, while there was no outgrowth on slices from bologna containing any of the additives. A consumer taste panel evaluated products containing the additives, and no differences in overall liking were found among the preparations of bologna. In conclusion, sodium levulinate was at least as effective at inhibiting outgrowth of L. monocytogenes in bologna as the current industry standards of lactate and lactate plus diacetate, and its addition did not alter the overall liking of the products.
Impacts
Listeria is pathogen of significant concern to the food industry, especially those industry segments producing ready-to-eat products such as processed meats and dairy products. This study will validate practical use of levulinic acid as a surface decontaminant for meat, and levulinate as an antilisterial additive for ready-to-eat meat products. The project will also investigate the cellular mechanism(s) for the susceptibility of Listeria to levulinate and two other important organic acid anions, lactate and acetate. This project will enhance the safety of meats by adding to the arsenal of scientifically-sound strategies used to control growth of many food-borne pathogens.
Publications
- Allen, K. E., Carpenter,C. E., Walsh, M. K. 2007. Influence of protein level and starch type on extrusion-expanded whey product. Int. J. Food Sci. Tech. 42:953-960.
- Carpenter, C.E., Broadbent, J.B. 2006. Method of inhibiting growth of Listeria monocytogenes using levulinate. Patent filed August 2007 :.
- Taylor, D.P., Carpenter, C. E. and Walsh. M. K 2006. Influence of sulfonation on the properties of expanded extrudates containing 32% whey protein. J. Food Sci. 71 :Nr 2, E17-24.
- John, L., Cornforth, D. P., Carpenter, C. E., Sorheim, O., Pettee, B. and Whittier, D. 2005. Color and thiobarbituric acid values of cooked top sirloin steaks packaged in modified atmoshperes of 80% oxygen, or 0.4% corbon monoxide, or vacuum. Meat Sci. 69:441-449.
- John, L., Cornforth, D.P., Carpenter, C.E., Sorheim, O., Pettee, B.C., Whittier, D.R. 2004. Comparison of color and thiobarbituric acid values of cooked hamburger patties after storage of fresh beef chubs in modified atmospheres . J. Food Sci. 69:C608-614.
- Vasavada, M.N. 2004. Comparative effects of sodum levulinate and sodium lactate on microbial growth, color, and thiobarbituric acid (TBA) values of fresh pork and turkey sausage during storage. MS thesis, Dept. of Nutrition & Food Science :.
- Taylor, D.P. 2004. Investigation of the effect of sulfitolysis on the functional properties and extrusion performance of whey protein concentrate. Ph.D. Dissertation, Dept. of Nutrition & Food Science.
- Walsh, M.K., Carpenter, C.E. 2003. Textured whey protein product and method. US Patent No. 6,607,777.
- Vasavada, M. N., C. E. Carpenter, D. P. Cornforth, Ghorpade,V. 2003. Sodium levulinate and sodium lactate effects on microbial growth and stability of fresh pork and turkey sausages during storage. J. Muscle Foods 14:119-129.
|
Progress 01/01/06 to 12/31/06
Outputs
Slices of turkey roll were inoculated with a 5-strain cocktail of Listeria monocytogenes, vacuum packaged, and stored at 2oC for 0-12 weeks. Samples were collected biweekly and analyzed for growth of L. monocytogenes. Counts of L. monocytogenes in untreated control meat exceeded 1010 cfu per mL of recovery solution after 8 weeks, and remained above 109 cfu/mL after 12 weeks. Turkey roll that contained 2% sodium lactate, 1% sodium levulinate, or 2% sodium lactate/diacetate mixture showed growth of the pathogen after 4, 6, or 10 weeks, respectively. In comparison, turkey roll that contained 2% or 3% sodium levulinate inhibited growth of L. monocytogenes throughout the 12 week storage period. Members of a consumer panel tasted turkey rolls containing 0, 2.0, or 3.0% of sodium levulinate, 2% sodium lactate, and 2.0% mix of sodium lactate and diacetate. Evaluations were recorded using a hedonic scale of 1 -9, with 1 = strongly dislike, 5 = neither like nor dislike, and 9 =
strongly like. The data was analyzed by statistical ANOVA, and treatment means were compared at p <= 0.05. There were no differences in overall liking for the various turkey samples. In conclusion, sodium levulinate was more effective at preventing growth of L. monocytogenes in turkey roll than the current industry standards of lactate or a mix of lactate and diacetate, and addition of sodium levulinate did not alter the acceptability of this ready-to-eat meat product.
Impacts
This project will enhance the safety of ready-to-eat processed meats by adding to the arsenal of scientifically-sound strategies used to control growth of many food-borne pathogens.
Publications
- Taylor, D.P., Carpenter, C. E. and Walsh. M. K. 2006. Influence of sulfonation on the properties of expanded extrudates containing 32
|
Progress 01/01/05 to 12/31/05
Outputs
In preface to the bacterial challenge studies for objective 1, the following Listeria strains were obtained from ILSI North American Database housed at Cornell University: FSL J1-177 - ribotype DUP-1051D, lineage I, serotype 1/2b, isolated from human sporadic case; FSL C1-056 - ribotype DUP-1030A, lineage II, serotype 1/2a; isolated from human sporadic case; FSL N3-013 - ribotype DUP-1042B, lineage I, serotype 4b, food isolate associated with human listeriosis epidemic in the UK (1988-1990); FSL R2-499 - ribotype DUP-1053A, lineage II, serotype 1/2a, human isolate associated with US outbreak linked to sliced turkey (2000); FLS N1-227 - ribotype DUP-1044A, lineage I, serotype 4b, food isolate associated with US outbreak (1998-1999). In order to document the identity the bacterial strains, we performed several tests on each strain of Listeria moncytogenes, and on our lab strain of Listeria innocua. These tests included Gram staining and plating on Bio-Rad RAPID'L.Mono
selective agar. We also isolated template DNA from each strain and performed PCR with universal primers for 16S ribosomal DNA. PCR products were purified using Amicon Micron PCR centrifugal filter devices, then sequenced. The strains were identified according to their 16S ribosomal DNA sequence (performed by MC Labs, South San Francisco, CA). The results from each of these tests confirmed the expected identity all strains. Also in preface to the challenge studies for objective 1, we evaluated our methods to inoculate and recover Listeria. Using commercial bologna and turkey breast and L. inocua, we established a protocol for inoculation of the meat products and documented the effectiveness of our recovery procedure at 1 - 24% recovery for the bologna and 3 - 26% recovery for turkey. These recoveries were after incubation times from 2 hours to 4 days, with the greatest recoveries after short incubations. These recoveries appear well within reasonable expectation, especially given that
commercial bologna and turkey breast contain sodium lactate and sodium diacetate as antibacterial controls, which are likely inhibiting or killing the Listeria and lowering recovery rates at the longer times.
Impacts
This project will enhance the safety of ready-to-eat processed meats by adding to the arsenal of scientifically-sound strategies used to control growth of many food-borne pathogens.
Publications
- John, L., Cornforth, D. P., Carpenter, C. E., Sorheim, O., Pettee, B. and Whittier, D. 2005. Color and thiobarbituric acid values of cooked top sirloin steaks packaged in modified atmoshperes of 80
|
|