Submitted to: Journal of Food Protection
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: 4/16/2004
Publication Date: 10/20/2004
Citation: Bosilevac, J.M., Shackelford, S.D., Fahle, R., Biela, T., Koohmaraie, M. 2004. Decreased dosage of acidified sodium chlorite reduces microbial contamination and maintains organoleptic qualities of ground beef products. Journal of Food Protection 67:2248-2254.
Interpretive Summary: Bacteria on the surface of boneless beef trimmings used to make ground beef are mixed into the center of the meat during the process of grinding. Controlling this contamination is a high priority because these bacteria may not be killed during cooking, and one potential bacterial contaminant is E. coli O157:H7, a pathogen that can cause life-threatening infections. A number of treatments have been designed to reduce contamination in ground beef that target the trimmings from which it is made. Many treatments, however, affect the color and taste of the ground beef, resulting in product that is not appealing to consumers. This work examines the use of a broad-spectrum disinfectant, acidified sodium chlorite (ASC), as an alternative treatment to reduce the level of contamination of boneless beef trim and ground beef while maintaining desirable consumer traits. The previously described dosage of ASC reduces contamination, but also results in discolored and non-typical tasting ground beef. The goal of this work was to determine if decreased doses of ASC would still result in acceptable decontamination as measured by two bacterial counts, aerobic plate counts (APC) and Enterobacteriaceae counts (EBC), and maintain desirable odor, color, and taste as measured by a consumer taste panel. Two decreased concentrations of ASC were used (a medium dose and a low dose) to treat beef trimmings before grinding. Treatment of the trimmings with ASC reduced both the APC and EBC by 90% or more. The treated trimmings were ground into 90 percent and 73 percent lean ground beef that was stored in two types of commercial packaging (chubs and modified atmosphere packaging). The organoleptic qualities (color, odor, and taste) of the ground beef treated with the lowest ASC concentration were not different than non-treated ground beef, whereas the qualities of the ground beef treated with a medium dose of ASC were less desirable. The efficacy of ASC on APC and EBC over the shelf life of the ground beef was monitored. Both treatments with ASC controlled the growth of EBC, which did not increase. APC increased over time in the treated ground beef, but not to the extent that occurred in non-treated ground beef, suggesting favorable effects on shelf life.
Technical Abstract: Acidified sodium chlorite (ASC) spray was evaluated at decreased dosages and application rates to determine its efficacy for reducing bacterial contamination on boneless beef trimmings used for production of raw ground beef products, while maintaining desirable consumer qualities in the finished ground beef products. Two different applications of ASC were examined (600 ppm applied at a rate of 1.3 oz/lb and 300 ppm applied at a rate of 1 oz/lb) to treat two types of boneless beef trimmings before grinding. The effect of ASC treatment on 50/50 lean beef trimmings was greater than on 90/10 trimmings. 600 ppm ASC reduced both the aerobic plate counts (APC) and Enterobacteriaceae counts (EBC) by 2.3 log10 CFU/g on 50/50 trimmings, whereas treatment with 300 ppm ASC reduced APC and EBC of 50/50 trimmings by 1.1 and 0.7 log10 CFU/g, respectively. Ground beef formulations of 90/10 and 73/27 were produced from the treated boneless beef trim and packaged in chubs and in modified atmospheric packaging (MAP). The efficacy of ASC spray treatment to inhibit APC and EBC over the shelf life of each ground beef product was monitored. The APC and EBC in ground beef chubs were reduced by 1 to 1.5 log10 CFU/g until day 20. The APC and EBC for MAP products were reduced 1.5 to 3.0 log10 CFU/g throughout their shelf life. Both decreased dosages of ASC were equally effective on 90/10 lean ground beef, but the 300 ppm ASC treatment was slightly better at reducing EBC of 73/27 ground beef. The organoleptic qualities (color, odor, and taste) of the 300 ppm ASC-treated ground beef products were found to be superior to those of the 600 ppm ASC-treated ground beef. Our results indicate that reduced dosages of ASC can reduce contamination and lengthen the shelf life of ground beef. Further, the 300 ppm ASC treatment reduces bacterial counts while maintaining desirable organoleptic ground beef qualities.