Effect of different concentrations of acetic, citric, and propionic acid dipping solutions on bacterial contamination of raw chicken skin

Authors: MENCONI, ANITA - University Of Arkansas; SHIVARAMAIAH, CHAITANYA - University Of Arkansas; Huff, Geraldine; PRADO, OMAR - Universidad De Colima; MORALES, EDUARDO - Universidad Autonoma De Baja California; PUMFORD, NEIL - University Of Arkansas; MORGAN, MARION - University Of Arkansas; WOLFENDEN, AMANDA - University Of Arkansas

Submitted to: Poultry Science
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: 5/11/2013
Publication Date: 8/1/2013
Citation: Menconi, A., Shivaramaiah, C., Huff, G.R., Prado, O., Morales, E., Pumford, N., Morgan, M., Wolfenden, A.D. 2013. Effect of different concentrations of acetic, citric, and propionic acid dipping solutions on bacterial contamination of raw chicken skin. Poultry Science. 92(8):2216-2220.

Interpretive Summary: Bacterial contamination of raw, processed poultry may include spoilage bacteria and foodborne pathogens. We evaluated different combinations of organic acid (OA) wash solutions for their ability to reduce bacterial contamination of raw chicken skin and to inhibit growth of spoilage bacteria and pathogens on skin during refrigerated storage. In experiment 1, raw chicken skin samples were dipped into a a culture of Salmonella Typhimurium (ST), Escherichia coli O157:H7 (EC), or Listeria monocytogenes (LM) for 30 s and then immersed in either phosphate buffered saline (PBS) or an OA wash solution mixture of 0.8 % citric, 0.8 % acetic, and 0.8 %) propionic acid (equal percentages) for an additional 30 s. In experiment 2, three different concentrations of the OA wash solution (0.2, 0.4, and 0.6 %) were tested against chicken skin samples contaminated with ST. Viable pathogenic bacteria on each skin sample were counted after 1 and 24 h of storage at 4C in both experiments. In experiment 3, skin samples were initially treated on day one with either PBS or two concentrations of the OA mixture (0.4 % and 0.8 %) and total aerobic bacteria were counted during a two week storage period. In all experiments, significant differences were observed when skin samples were treated with the OA wash solution and no spoilage organisms were recovered at any given time-point, while increasing numbers of spoilage organisms were recovered over time in PBS treated skin samples. These results suggest that 0.2 - 0.8 % concentrations of an equal-percentage mixture of this OA combination may reduce pathogens and spoilage organisms and improve food safety properties of raw poultry.

Technical Abstract: Bacterial contamination of raw, processed poultry may include spoilage bacteria and foodborne pathogens. We evaluated different combinations of organic acid (OA) wash solutions for their ability to reduce bacterial contamination of raw chicken skin and to inhibit growth of spoilage bacteria and pathogens on skin during refrigerated storage. In experiment 1, raw chicken skin samples were dipped into a suspension of either 10E8 cfu/mL of Salmonella Typhimurium (ST), Escherichia coli O157:H7 (EC), or Listeria monocytogenes (LM) for 30 s and then immersed in either phosphate buffered saline (PBS) or an OA wash solution mixture of 0.8 % citric, 0.8 % acetic, and 0.8 % propionic acid (at equal w/v concentrations) for an additional 30 s. In experiment 2, three different concentrations of the OA wash solution (0.2, 0.4, and 0.6 % at equal w/v concentrations) were tested against chicken skin samples contaminated with ST. Viable pathogenic bacteria on each skin sample were enumerated after 1 and 24 h of storage at 4C in both experiments. In experiment 3, skin samples were initially treated on day one with either PBS or two concentrations of the OA mixture (0.4 % and 0.8 %) and total aerobic bacteria were enumerated during a two week storage period. In all experiments, significant (p < 0.05) differences were observed when skin samples were treated with the OA wash solution and no spoilage organisms were recovered at any given time-point, while increasing log10 numbers of spoilage organisms were recovered over time in PBS treated skin samples. These results suggest that 0.2 - 0.8 % concentrations of an equal-percentage mixture of this OA combination may reduce pathogens and spoilage organisms and improve food safety properties of raw poultry.