|Kang, Dong Hyun|
Submitted to: Journal of Food Protection
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: 8/18/2000
Publication Date: N/A
Interpretive Summary: Deboned beef trim is the material used for producing ground beef. Currently, after deboning from the beef carcass, no antimicrobial treatments are applied to the material other than refrigeration. We have developed an antimicrobial treatment process for beef trim to be used immediately prior to the trim being boxed for shipment to grinding facilities. This process is actually a series of multiple processing steps that, when combined as a single process, gives better microbial inhibition of fecal bacterial contaminants than individual antimicrobial interventions. This process incorporates a high pressure water wash, followed by a hot water spray, then a hot air treatment finished with an ambient temperature spray of 2.0% foodgrade lactic acid. This multi-step treatment had negligible color-quality effects on the final ground beef patty. Following treatment and storage of lean beef trim at 5 deg C for up to 7 days, the numbers of coliform (fecal) bacteria and biotype 1 Escherichia coli decreased an average of more than 90%, then remained at constant levels. Microbial reductions were considerably higher in the case of fat beef trim (99.9% reduction). Such multi-hurdle approaches offer processors a final guard against proliferation and transmission of pathogenic bacteria prior to grinding.
Technical Abstract: Multiple hurdle antimicrobial processes for beef trim were developed and tested on inoculated lean beef trim tissue (BTL) and fat covered lean trim (BTF) during refrigerated storage following different multi-hurdle antimicrobial treatments. Treatments included: C (Control, no treatment), W (water wash at 65 psi for 5 s/cm ), WL (W + L [2% v/v lactic acid wash at 30 psi for 3 s/cm]), comb 1 (W + HW [65 deg C hot water at 30 psi for 1 s/cm] + HA [hot air at 510 deg C for 4 s/cm] + L), comb 2 (W + HW [82 deg C for 1 s/cm] + HA [510 deg C for 5 s/cm] + L), and comb 3 (W + HW [65 deg C for 3 s/cm] + HA [510 deg C for 6 s/cm] + L). Treatment effects were monitored by measuring mesophilic aerobic bacteria (APC), presumptive lactic acid bacteria (PLAB), psychrotrophic bacteria (PCT), coliforms, and biotype 1 Escherichia coli. In the case of BTL, the numbers of APC, PCT, and PLAB increased during storage at 5 deg C to 7 days, whereas the numbers of coliform and E. coli decreased an average of 1.8 log CFU/cm2 then remained constant. Negligible effects on color quality were observed from multi-hurdle treatment comb 1. In the case of the BTF, the microbial reductions by treatments were much greater than the reduction on BTL. The pH of treated BTF increased more slowly than the pH of treated BTL, resulting in further reduction of microflora on BTF. Except C and W treatments, all sample treatments containing lactic acid resulted in continuously decreasing microbial populations. Based on microbial reduction and quality aspects, combination 1 was identified as a favorable multi-hurdle antimicrobial trim intervention from this study.