Purpose: This study validated the efficacy of two lauric arginate (LAE) solutions [Mirenat-GA (M) and Cytoguard LA20 (C)] as an in-bag subprimal treatment, followed by a peroxyacetic acid (PAA; 200 ppm solution) spray upon re-opening vacuum bags for mechanical tenderization, to reduce STEC-7 populations.
Methods: Beef striploins were inoculated with a STEC-7 cocktail to achieve 5 log CFU/cm2. Four primary treatments (M+tap water, M+deionized water, C+tap water, and C+deionized water) were evaluated using seven application concentrations (0, 50, 100, 150, 200, 250 and 500 ppm) per kilogram of meat treated. Treatments were applied to loin surfaces within Cryovac bags immediately before vacuum sealing, allowing the natural purge of the vacuum-packaged subprimal to distribute the antimicrobial. Packaged product was stored at 4°C for 24 or 48 h, then removed from bags and sprayed with PAA. STEC populations were determined post-inoculation before treatments, post-chill period, and post-PAA treatment. The statistical analysis was done using SAS 9.4 and was a repeated measures analysis.
Results: No differences (P > 0.05) were found among the primary LAE treatments; thus, observations were pooled to evaluate concentration effects. STEC reductions greater (P ≤ 0.05) than the 0 ppm control were seen at ≥ 200 ppm LAE, with no differences observed between solution sources. Overall STEC-7 reductions were ~1.2 log CFU/cm2 at ≥ 200. No additional STEC population reductions were achieved by applying 200 ppm PAA to chilled subprimals.
Significance: This research validated an in-bag intervention strategy that could be applied by the beef industry to help reduce STEC risk in enhanced/tenderized beef products.