title: The antimicrobial effect of oregano essential oil, nisin and their combination against Salmonella Enteritidis in minced sheep meat during refrigerated storage.
abstract: The antimicrobial effect of oregano essential oil (EO) at 0.6 or 0.9%, nisin at 500 or 1000 IU/g, and their combination against Salmonella Enteritidis was studied in minced sheep meat during storage at 4 degrees or 10 degrees C for 12 days. Sensory evaluation showed that the addition of oregano EO at 0.6 or 0.9% in minced sheep meat was organoleptically acceptable, and attribute scores were higher for the EO at 0.6 than 0.9%. According to compositional analysis of the oregano EO, the phenols carvacrol (80.15%) and thymol (4.82%) were the predominant components. Treatment of minced sheep meat with nisin at 500 or 1000 IU/g, proved insufficient to act against S. Enteritidis. The combination of the oregano EO at 0.6% with nisin at 500 IU/g showed stronger antimicrobial activity against S. Enteritidis than the oregano EO at 0.6% but lower than the combination with nisin at 1000 IU/g, which in turn was lower than that of the oregano EO at 0.9%. In its turn, oregano EO at 0.9% showed lower antimicrobial activity than its combinations with nisin at 500 or 1000 IU/g, which showed a bactericidal effect against the pathogen. The inhibition percentages of all treatments against S. Enteritidis at 10 degrees C were higher than those at 4 degrees C.
authors.affiliation: Laboratory of Hygiene of Foods of Animal Origin, Faculty of Veterinary Medicine, University of Thessaly, 224 Trikalon Street, Karditsa, Greece. agovaris@vet.uth.gr
authors.forename: A
authors.initials: A
authors.lastname: Govaris
authors.forename: N
authors.initials: N
authors.lastname: Solomakos
authors.forename: A
authors.initials: A
authors.lastname: Pexara
authors.forename: P S
authors.initials: PS
authors.lastname: Chatzopoulou
mesh_terms: D000818:Animals; D000900:Anti-Bacterial Agents / Q000737:chemistry / Q000494:pharmacology*; D003080:Cold Temperature; D015169:Colony Count, Microbial; D000081007:Cymenes; D004347:Drug Interactions; D008460:Meat / Q000382:microbiology*; D039821:Monoterpenes / Q000032:analysis; D009561:Nisin / Q000494:pharmacology*; D009822:Oils, Volatile / Q000737:chemistry / Q000494:pharmacology*; D031341:Origanum / Q000737:chemistry*; D012034:Refrigeration; D012477:Salmonella enteritidis / Q000187:drug effects*; D012756:Sheep; D013943:Thymol / Q000032:analysis
chemical_list: D000900:Anti-Bacterial Agents; D000081007:Cymenes; D039821:Monoterpenes; D009822:Oils, Volatile; D009561:Nisin; D013943:Thymol; C073316:carvacrol