PERSPECTIVES ON THE USE OF ESSENTIAL OILS AS ANTIMICROBIALS AGAINST CAMPYLOBACTER JEJUNI CECT 7572 IN RETAIL CHICKEN MEATS PACKAGED IN MICROAEROBIC ATMOSPHERE

摘要

The chemical composition of the essential oils (EOs) of Inula graveolens, Laurus nobilis, Pistacia lentiscus and Satureja montana was analyzed using a gas chromatography-mass spectrometry technique. The main components of EOs obtained were, respectively, bornyl acetate, 1,8-cineole, beta-myrcene and carvacrol. EOs were screened for their ability to inhibit the growth of Campylobacter jejuni CECT 7572 using the standard agar-disk diffusion assay. The results obtained, followed by measurements of minimal inhibitory concentrations, indicated that I. graveolens was most active (PHI = 53.3 mm), with the lowest MIC value against C. jejuni (2 mu L/mL). EOs were tested in chicken stored in microaerobic conditions at 3 ± 2C, experimentally inoculated with the pathogen at a level of 5 × 105 cfu/g. C. jejuni counts in treated samples were 0.7–4.7 log10 cfu/g lower (P < 0.05) than the controls throughout storage. The latter reached numbers of about 8 log10 cfu/g after 1 week. Lipid oxidation (thiobarbituricacid reactive substances [TBARS]) and sensory freshness odor were also determined. Samples treated with any EO had the lowest TBARS values (P < 0.05). The presence of EOs significantly extended fresh meat odor. The results of the bioassays, together with the chemical profile of the EOs, support the possibility of using all EOs as potent natural preservatives to contribute in the reduction of experimentally inoculated C. jejuni in chicken meat.