Efficacy of lactic acid against Listeria monocytogenes attached to poultry skin during refrigerated storage.
OBJECTIVE
The aim of this study was to evaluate the effect of lactic acid washing on the growth of Listeria monocytogenes on poultry legs stored at 4 degrees C for 7 days.


RESULTS
Fresh inoculated chicken legs were dipped into either a 0.11, 0.22 mol l(-1) or 0.55 mol l(-1) lactic acid solution for 5 min or distilled water (control). Surface pH values, sensorial characteristics and L. monocytogenes, mesophiles and pychrotrophs counts were evaluated after treatment (day 0) and after 1, 3, 5 and 7 days of storage at 4 degrees C. Legs washed with 0.55 mol l(-1) lactic acid for 5 min showed a significant (P < 0.05) inhibitory effect on L. monocytogenes compared with control legs, being about 1.74 log units lower in the first ones than in control legs after 7 days of storage. Sensory quality was not adversely affected by lactic acid, with the exception of colour.


CONCLUSIONS
Treatments with 0.55 mol l(-1) lactic acid reduced bacterial growth and preserved reasonable sensorial quality after storage at 4 degrees C for 7 days. However, it was observed a reduction in the colour score within 1 day post-treatment with 0.55 mol l(-1) lactic.


CONCLUSIONS
This study demonstrates that, while lactic acid did reduce populations of L. monocytogenes on poultry, it did not completely inactivate the pathogen. The application of lactic acid may be used as an additional hurdle contributing to extend the shelf-life of raw poultry.
González-Fandos
E
E
Food Technology Department. University of La Rioja, La Rioja, Spain. elena.gonzalez@daa.unirioja.es
Dominguez
J L
JL
D000818:Animals; D002645:Chickens / Q000382:microbiology*; D015169:Colony Count, Microbial; D005519:Food Preservation; D006863:Hydrogen-Ion Concentration; D019344:Lactic Acid / Q000494:pharmacology*; D008089:Listeria monocytogenes / Q000187:drug effects* / Q000502:physiology; D012034:Refrigeration; D012867:Skin / Q000382:microbiology*; D012880:Skin Pigmentation; D013997:Time Factors
D019344:Lactic Acid