Report Comparing Efficacy of Beefxide® and Lactic Acid Solutions

Location and Date of Testing:

Testing was conducted at the Tarleton State University Meat Laboratory during March 2009. Tarleton is a member of The Texas A&M University System.

Test and Sampling Procedure:

Six steers were harvested following standard meat lab protocols according to HACCP and SSOPs. After each carcass had been split into sides, each side was initially trimmed free of visible fecal, milk or ingesta and then rinsed with tap water. Swab samples were collected from the rump, flank, and brisket prior to the application of the antimicrobial solution. Microbial samples were tested for aerobic coliform and E. coli organisms. The left side of each carcass was sprayed with a 2.5 % solution of Birko Beefxide® (3.2 fl. oz. per gallon). The solution was applied at ambient temperature until the entire carcass was dripping with the solution. Following the same swab sampling protocols, the right side of each carcass was sprayed with a 5 % solution of lactic acid (6.4 fl oz per gallon). The solutions were applied at ambient temperature until the entire carcass was dripping with the solution. The solutions were applied to the sides with a hand sprayer before carcasses were placed in the hot box. A second collection of samples were taken from the same anatomical areas 30 minutes after the initial application of the antimicrobial solutions. In order to obtain statistical results that are valid, repeatable, accurate, and are true representatives of the population, statistical analysis will be conducted using the Statistical Analysis System. For microbial data, Proc MIXED of SAS with repeated measures will be used. Least square means will be estimated using the LSMEANS statement and when significant effects are detected (P< 0.05), the PDIFF option will be used for mean separation. Paired T-tests were conducted when comparing means for either Pre and Post application of the solutions as well as comparing the two solutions.

Results

Log reduction numbers reflect the efficacy of both Beefxide and Lactic Acid and their effects on microorganisms relating to the carcass. When the data were pooled for both Beefxide and Lactic Acid, they significantly reduced microbial numbers from 3.0085 log 102 on Pre treatment carcasses to 0.8345 log 102 for the Post treatment carcasses. This reduction was significant (P<0.0001).

Log reduction numbers reflect the efficacy of both Beefxide and Lactic Acid and their effects on microorganisms relating to the carcass. When the means for both Beefxide and Lactic Acid were separated, they again showed significantly reduced microbial numbers. Following the treatment with Beefxide, microbial numbers were reduced from 2.948 log 102 on Pre treatment carcasses to 0.9866 log 102 for the Post treatment carcasses. Furthermore, after the treatment with Lactic Acid, microbial numbers were reduced from 3.069 log 102 on Pre treatment carcasses to 0.6824 log 102 for the Post treatment carcasses. These reductions were significant (P<0.0001).

When comparing log reduction means for Beefxide against Lactic Acid for post treatment only, there was no significances reported (P > 0.05).

Summary:

Both Beefxide and Lactic Acid solution treatments were effective for reducing microbial numbers as an antimicrobial treatment for hot beef carcasses. In addition, when Beefxide was compared to Lactic Acid for post treatment only, there was no significance reported. However, the sample size was only six carcasses and thus it is recommended that we continue accumulating data for an increased sample size. Also, we recommend changing the protocol by using 180 degree F water for the rinse prior to sampling instead of tap water as well as quantifying the amount of solution applied to each side.