Multiple fluorescence labelling of proteins, lipids and whey in dairy products using confocal microscopy

Texture optimisation of dairy products is a major aim for manufacturers. A better knowledge of the structure and spatial organisation of their main co mponents would allow the optimisation of their texture. In this study, usin g confocal scanning laser microscopy, a multiple fluorescent labelling of p roteins, lipids and whey was developed to visualise these main components s imultaneously in dairy products. Different extrinsic fluorescent probes wer e tested by confocal microscopy and fluorescence spectroscopy. Fuchsin acid , Bodipy(R) 665/676 and DM-NERF were selected to label proteins, lipids and whey, respectively. Methods for selecting stable and specific fluorescent probes and for obtaining the multiple fluorescent labelling are presented. An application example on a dairy gel is also shown. (C) Inra/Elsevier, Par is.