|Kang, Dong Hyun|
Submitted to: Journal of Food Protection
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: 9/10/2000
Publication Date: N/A
Interpretive Summary: We have recently 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 (high pressure water wash, followed by a hot water spray, then a hot air treatment finished with an ambient temperature spray of 2.0 percent foodgrade lactic acid) that, when combined as a single process, gives better microbial inhibition of fecal bacterial contaminants than individual antimicrobial interventions. The current study indicates that the multi-hurdle process is also effective on actual beef trim from a commercial beef processor. This included beef trim of many different shapes, sizes, fat/lean compositions and geometric configurations and, therefore, was representative of actual trim within a plant. The current data reduced coliform bacterial counts by 99 percent over approximately one week of refrigerated storage. With some engineering optimizations, this process could be usable in beef trim production lines for reduction of fecal bacteria as well as prolonged antimicrobial action in meat trim.
Technical Abstract: Commercially produced, irregular size uninoculated beef trim was treated by a previously optimized multi-hurdle antimicrobial process: W (water wash at 65 psi for 5 s/cm) + HW (82 deg C water at 30 psi for 3 s/cm) + HA (510 deg C air for 6 s/cm) + L (2 percent vol/vol lactic acid wash at 30 psi for 3 s/cm). After treatment, the trim was finely ground, vacuum packaged, and dstored at 4 deg C for up to 20 days. At regular intervals (0, 5, 10, 15, and 20 days of storage at 4 deg C), the ground beef was analyzed to measure mesophilic aerobic bacteria (APC), coliforms, psychrotrophic bacteria (PCT) and presumptive lactic acid bacteria (PLAB) and compared with untreated control. Immediately after treatment, the numbers of APC, coliforms, PCT, and PLAB were reduced to nearly non-detectable levels with significant differences compared to control (P < 0.05), then started to increase after 5 to 10 days of incubation at 4 deg C. After 20 days, microbial populations of treated ground beef were significantly lower than those of non-treated ground beef for the numbers of APC, coliforms, PCT, and PLAB (P < 0.05). Based on microbial reduction and quality aspects, the multi- hurdle antimicrobial process was identified as an effective intervention to reduce coliforms on beef trim. The multi-hurdle antimicrobial treatment reduced the numbers of coliforms by 2.4 log unit after 20 days of storage at 4 deg C.