title: Survival of Campylobacter jejuni in different gas mixtures.
abstract: Campylobacter jejuni in fresh chilled chicken meat is known to be a major risk factor for human gastrointestinal disease. In the present study, the survival under chilled conditions of different C. jejuni strains exposed to different gas mixtures usually used for gas packaging of food was examined. Bolton broth and fresh, skinless chicken fillets were inoculated with six and four strains, respectively, and exposed to the gas mixtures 70/30% O(2)/CO(2), 70/30% N(2)/CO(2), and 100% N(2) (the latter only investigated in broth) at refrigeration temperature (4-5 degrees C). In broth culture, the strains survived significantly longer when exposed to 100% N(2) and 70/30% N(2)/CO(2) than in the oxygen-containing gas mixture, 70/30% O(2)/CO(2) (P<0.0001). For the two anaerobic gas mixtures, the reductions only reached 0.3-0.8 log(10) CFU mL(-1) within the same period. In the presence of oxygen, the numbers of C. jejuni were reduced by a minimum of 4.6 log(10) CFU mL(-1) over 21 days. When inoculated onto chicken fillets, the C. jejuni strains also died significantly faster in the oxygen-containing gas mixture, 70/30% O(2)/CO(2) (P<0.0001), reaching reductions of 2.0-2.6 log(10) CFU g(-1) after 8 days. In the gas mixture without oxygen (70/30% N(2)/CO(2)), no reductions were observed.
authors.affiliation: Department of Microbiology and Risk Assessment, Danish Institute for Food and Veterinary Research, Soeborg, Denmark.
authors.forename: Louise
authors.initials: L
authors.lastname: Boysen
authors.forename: Susanne
authors.initials: S
authors.lastname: Knøchel
authors.forename: Hanne
authors.initials: H
authors.lastname: Rosenquist
mesh_terms: D000818:Animals; D016123:Campylobacter jejuni / Q000187:drug effects* / Q000254:growth & development; D002245:Carbon Dioxide / Q000494:pharmacology; D002645:Chickens / Q000382:microbiology; D015169:Colony Count, Microbial; D005516:Food Microbiology; D005740:Gases / Q000494:pharmacology*; D008460:Meat / Q000382:microbiology*; D050296:Microbial Viability / Q000187:drug effects*; D009584:Nitrogen / Q000494:pharmacology; D010100:Oxygen / Q000494:pharmacology
chemical_list: D005740:Gases; D002245:Carbon Dioxide; D009584:Nitrogen; D010100:Oxygen