Purpose: This project was designed to validate in-plant application of two different antimicrobial interventions (lactic acid and Beefxide) applied to multiple processing schemes (e.g., single-pass or multiple-pass tenderization and marination).
Methods: Rifampicin-resistant Biotype I E. coli O157:H7 surrogate microorganisms (ATCC BAA-1427, BAA-1428, and BAA-1430) were applied as a cocktail (7.8 log CFU/ml) to three beef products (boneless strip loins, top sirloin butts, and bottom sirloin flaps) prior to treatment with an antimicrobial intervention (2.5% Beefxide or 2.9% lactic acid). Following inoculation and antimicrobial spray, products were subjected to a single- or multiple-pass tenderization and/or marination process.
Results: Beefxide and lactic acid treatments resulted in statistically significant (P < 0.05) log reductions of surrogate microorganisms on product surfaces for all three beef subprimals. Surrogate microorganisms also were recovered from interior samples of all three beef product types after mechanical tenderization. Additionally, there were no statistical differences (P > 0.05) between the post-treatment surface and interior counts for the bottom sirloin flap following tenderization and marination.
Significance: These data indicate that tenderization and marination processes can transfer microorganisms into the interior of whole-muscle cuts, and suggest Beefxide and lactic acid may be similar in their efficacy as an antimicrobial applied as an intervention in the production of non-intact beef products.