title: Biopreservation of hamburgers by essential oil of Zataria multiflora.
abstract: Hamburgers with high nutrient supply and a loosely-packed structure present favourable conditions for microbial growth. In this study, the chemical composition and antimicrobial activity of the essential oil of Zataria multiflora and its potential application as a natural preservative in reducing the indigenous microbial population of hamburgers were investigated. Carvacrol, thymol and linalool were found to be the most abundant constituents of the essential oil using GC-MS analysis. The essential oil exhibited strong antibacterial activity against Gram-positive and Gram-negative bacteria. Addition of Z. multiflora essential oil in concentrations higher than MIC values influenced the microbial population of hamburgers stored at 25°C, 4°C and -12°C. The significant results of this study are our observations that the use of Z. multiflora essential oil at 0.05% v/w increases the time needed for the natural microflora of hamburgers to reach concentrations able to produce a perceivable spoilage at refrigerator and room temperatures without any inverse effect on their sensory attributes. Freezing of essential oil-treated hamburgers may also reduce the risk of diseases associated with consumption of under-cooked hamburgers through significant microbial reduction by more than 3 log.
authors.affiliation: Department of Drug and Food control, Faculty of Pharmacy and Pharmaceuticals Quality Assurance Research Center, Tehran University of Medical Sciences, Tehran, Iran. samadin@sina.tums.ac.ir
authors.forename: N
authors.initials: N
authors.lastname: Samadi
authors.forename: A
authors.initials: A
authors.lastname: Sharifan
authors.forename: Z
authors.initials: Z
authors.lastname: Emam-Djomeh
authors.forename: M H Salehi
authors.initials: MH
authors.lastname: Sormaghi
mesh_terms: D000080462:Acyclic Monoterpenes; D000900:Anti-Bacterial Agents / Q000737:chemistry / Q000494:pharmacology; D000081007:Cymenes; D008401:Gas Chromatography-Mass Spectrometry; D006090:Gram-Negative Bacteria / Q000187:drug effects; D006094:Gram-Positive Bacteria / Q000187:drug effects; D019686:Lamiaceae / Q000737:chemistry*; D008826:Microbial Sensitivity Tests; D039821:Monoterpenes / Q000737:chemistry / Q000494:pharmacology; D009822:Oils, Volatile / Q000737:chemistry* / Q000494:pharmacology; D035261:Plant Components, Aerial / Q000737:chemistry; D013943:Thymol / Q000737:chemistry / Q000494:pharmacology
chemical_list: D000080462:Acyclic Monoterpenes; D000900:Anti-Bacterial Agents; D000081007:Cymenes; D039821:Monoterpenes; D009822:Oils, Volatile; D013943:Thymol; C073316:carvacrol; C018584:linalool