Effect of propionic acid on Campylobacter jejuni attached to chicken skin during refrigerated storage.

The ability of propionic acid to reduce Campylobacter jejuni on chicken legs was evaluated. Chicken legs were inoculated with Campylobacter jejuni. After dipping legs in either water (control), 1% or 2% propionic acid solution (vol/vol), they were stored at 4ºC for 8 days. Changes in C. jejuni, psychrotrophs and Pseudomonas counts were evaluated. Washing in 2% propionic acid significantly reduced C. jejuni counts compared to control legs, with a decrease of about 1.62 log units after treatment. Treatment of chicken legs with 1 or 2% propionic acid significantly reduced numbers of psychrotrophs 1.01 and 1.08 log units and Pseudomonas counts 0.75 and 0.96 log units, respectively, compared to control legs. The reduction in psychrotrophs and Pseudomonas increased throughout storage. The highest reductions obtained for psychrotrophs and Pseudomonas counts in treated legs were reached at the end of storage, day 8, being 3.3 and 2.93 log units, respectively, compared to control legs. Propionic acid treatment was effective in reducing psychrotrophs and Pseudomonas counts on chicken legs throughout storage. It is concluded that propionic acid is effective for reducing C. jejuni populations in chicken. Copyright© by the Spanish Society for Microbiology and Institute for Catalan Studies.