Reciprocal Meat Conference Abstracts

Antimicrobial Effects of Peroxyacetic Acid Acidified with Various Acids when Applied to Inoculated Prerigor Beef Carcass Surface Tissue

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Abstract

ObjectivesTwo studies were conducted to evaluate the antimicrobial effects of blends of peroxyacetic acid (PAA) acidified with various acids against inoculated populations of nonpathogenic Escherichia coli biotype I surrogates for pathogenic E. coli and Salmonella on warm, prerigor beef carcass surface brisket tissue.Materials and MethodsIn phase I, 10 × 10 cm pieces (n = 10) of warm, prerigor beef carcass surface brisket tissue were inoculated (6 to 7 log CFU/cm2) with a 5-strain mixture of nonpathogenic E. coli biotype I surrogates. Samples were either left untreated (control) or were immersed for 10 s in PAA (400 ppm) acidified with lactic acid (3.5%), PAA (400 ppm) acidified with acetic acid (2%), PAA (400 ppm) acidified with citric acid (1%), PAA (400 ppm) acidified with a sulfuric acid and sodium sulfate blend (pH 1.2 and pH 1.8; SSS), and PAA (300 ppm) acidified with SSS (pH 1.2). All samples were analyzed 5 min post-treatment for surviving Enterobacteriaceae populations. In phase II, 10 × 10 cm pieces (n = 10) of prerigor beef tissue inoculated (6 to 7 log CFU/cm2) with the same 5-strain mixture of nonpathogenic E. coli surrogates were either left untreated or were spray-treated (10 s) with water, PAA (350 ppm), PAA (400 ppm), PAA (400 ppm) acidified with acetic acid (2%), PAA (400 ppm) acidified with SSS (pH 1.2), or PAA (350 ppm) acidified with SSS (pH 1.2). Untreated and treated beef tissue samples were analyzed 5 min post-treatment for E. coli counts. Data were analyzed using the lsmeans package in R (Rstudio, 2015, Boston, MA) with antimicrobial treatment (including surfactant treatments) as the independent variable. Least-squares means were separated using a significance level of ɑ = 0.05.ResultsAll immersion treatments evaluated in phase I effectively (P < 0.05) reduced inoculated E. coli populations on the prerigor beef carcass surface tissue by at least 2.3 log CFU/cm2. The 400 ppm PAA treatments acidified with lactic acid, SSS (pH 1.2), or acetic acid were the most (P < 0.05) effective treatments, lowering inoculated bacterial counts from 6.2 log CFU/cm2 to 3.4, 3.4, and 3.7 log CFU/cm2, respectively. In phase II, all of the tested antimicrobial spray treatments effectively (P < 0.05) lowered initial inoculated E. coli counts (6.4 log CFU/cm2) by 1.7 to 1.9 log CFU/cm2. No (P ≥ 0.05) differences in efficacy were observed between the 5 antimicrobial treatments.ConclusionSince acidifying PAA with acetic acid or SSS is comparable to utilizing PAA, this could provide the industry with alternative antimicrobial intervention systems. Alternating the use of antimicrobials in a multiple-hurdle system could aid in the prevention of antimicrobial resistance.

Keywords: Escherichia coli, Beef, antimicrobial intervention

How to Cite:

Britton, B. C., Geornaras, I., Woerner, D. R., Delmore, R. J., Martin, J. N., Reagan, J. O. & Belk, K. E., (2018) “Antimicrobial Effects of Peroxyacetic Acid Acidified with Various Acids when Applied to Inoculated Prerigor Beef Carcass Surface Tissue”, Meat and Muscle Biology 2(2). doi: https://doi.org/10.221751/rmc2018.118