THE APPLICATION OF ELECTRON-MICROSCOPY IN DAIRY RESEARCH

A review is presented of the application of various electron microscopical techniques in dairy research. Special attention is given to the use of cryofixation techniques, such as freeze-fracturing, and of cryomicroscopy. These techniques are particularly well suited for the investigation of dairy products, which are mostly characterized by a high water content and by the presence of milk fat, having a low melting point. With these techniques, fat globules in milk, cheese and cream, and casein micelles in milk and milk products have been studied in an unperturbed state. By using immunogold-labelled cryosections it could be demonstrated that in casein micelles in milk the kappa-casein is located at the surface of the micelles, whereas the other caseins are distributed throughout the whole micelle.