Identification by fluorescence spectroscopy of lactic acid bacteria isolated from a small-scale facility producing traditional dry sausages.

Three different fluorescence spectra were recorded following excitation at 250 nm (aromatic amino acids+nucleic acids, AAA+NA), 316 nm (NADH) and 380 nm (FAD) for 20 type strain collections of lactic acid bacteria (LAB). Evaluation of the data using principal component analysis and factorial discriminant analysis showed a good discrimination of considered LAB at the genus, species and genus-species level. AAA+NA fluorophores showed the highest percentage of good classification. From AAA+NA spectra recorded on LAB isolated from a small-scale facility producing traditional dry sausages, we succeeded to identify 28 of 29 wild strains. This method allowed us to discriminate between Lactobacillus sakei subsp. carnosus and Lactobacillus sakei subsp. sakei. Thus, intrinsic fluorescence is an economical and powerful tool for the identification of wild LAB isolated from meat and meat products.