Validation of Lactic Acid as an Effective Antimicrobial Intervention for Beef Variety Meats

Introduction:  Lactic acid is an antimicrobial commonly applied to beef carcasses, primals/subprimals, and ground product to reduce spoilage and pathogenic bacteria. However, little is known about its effectiveness in variety meats.

Purpose: To determine the efficacy of a lactic acid spray on the reduction of microbiological indicators in beef variety meats.

Methods:  This study was conducted at a large beef processing plant in the Midwestern United States. Beef heads, hearts, and livers were subjected to a 4.5% lactic acid spay in a designated cabinet. In each of four replicates, 180 sponge samples were collected as follows: 90 before and 90 after antimicrobial intervention, with 30 swabs per meat component and 10 swabs per work shift (morning, midday, evening) being collected for pre- and posttreatment. For each sponge sample, Aerobic Plate Counts (APC), coliform counts (CC), and generic E. colicounts (EC) were estimated using 3M Petrifilms®. All Petrifilms® were incubated and read per manufacturer’s instructions.

Results:  Combined results from four replicates showed that in beef heads APC, CC, and EC were reduced by 2.9, 0.86, and 0.61 log CFU/cm², respectively. For livers, the before and after differences for APC, CC, and EC were 1.1, 0.66, and 0.39 log CFU/cm², respectively. Lastly, for hearts, average reductions were 1.3, 0.70, and 0.36 log CFU/cm², respectively. All differences were deemed significant at a 5% level of significance.

Significance:  Foreign markets absorb over 90% of the beef variety meats produced in the United States. Consequently, it is crucial that domestic processors validate and document the microbial safety and quality of their products to maintain the export status.