title: Identification of meat-associated pathogens via Raman microspectroscopy.
abstract: The development of fast and reliable sensing techniques to detect food-borne microorganisms is a permanent concern in food industry and health care. For this reason, Raman microspectroscopy was applied to rapidly detect pathogens in meat, which could be a promising supplement to currently established methods. In this context, a spectral database of 19 species of the most important harmful and non-pathogenic bacteria associated with meat and poultry was established. To create a meat-like environment the microbial species were prepared on three different agar types. The whole amount of Raman data was taken as a basis to build up a three level classification model by means of support vector machines. Subsequent to a first classifier that differentiates between Raman spectra of Gram-positive and Gram-negative bacteria, two decision knots regarding bacterial genus and species follow. The different steps of the classification model achieved accuracies in the range of 90.6%-99.5%. This database was then challenged with independently prepared test samples. By doing so, beef and poultry samples were spiked with different pathogens associated with food-borne diseases and then identified. The test samples were correctly assigned to their genus and for the most part down to the species-level i.e. a differentiation from closely-related non-pathogenic members was achieved.
authors.affiliation: Institute of Physical Chemistry and Abbe Center of Photonics, University of Jena, Helmholtzweg 4, D-07743 Jena, Germany.
authors.forename: Susann
authors.initials: S
authors.lastname: Meisel
authors.forename: Stephan
authors.initials: S
authors.lastname: Stöckel
authors.forename: Petra
authors.initials: P
authors.lastname: Rösch
authors.forename: Jürgen
authors.initials: J
authors.lastname: Popp
mesh_terms: D000818:Animals; D001419:Bacteria / Q000145:classification / Q000302:isolation & purification*; D002417:Cattle; D005506:Food Contamination / Q000032:analysis*; D005516:Food Microbiology; D008460:Meat / Q000032:analysis* / Q000382:microbiology*; D011200:Poultry; D013059:Spectrum Analysis, Raman / Q000379:methods*
keywords: Chicken breast; Food-borne pathogens; Minced beef; Raman microspectroscopy; Support vector machine; Three level classification model