EN
Modern fluorescent techniques and the possibilities of their application in food research are presented. Fluorescent dyes, fluorofores, are applied to the physiological state and viability research at the level of the single bacteria cell. DNA intercalators such as diamidino-2-phenylindole (DAPI) are frequently used for the enumeration of the bacteria population in food and plasma membrane integrity determination. Fluorogenic substrates allow the detection of the activity of the intercellular enzymes: esterases and dehydrogenases. The commercial set of fluorescent dyes LIVE/DEAD® BacLightTM Bacterial Viability Kit (Molecular Probes Inc) provides a simple assay for discriminating viable, metabolically active bacteria cells from injured and dead bacteria cells. The technique of fluorescent in situ hybridization (FISH) with the use of 16S rRNA or 23S rRNA-targeted fluorescent labelled oligonucleotide probes seems to be a promising tool for contemporary food microbiology. It can be used for the detection and identification of pathogenic bacteria in food or bacteria used in food production, such as lactic and propionic acid bacteria.