Microstructure of Liver Sausage

Cooked liver sausage was freeze-fractured and examined using scanning electron microscopy after fixation in either Zenker's solution or osmium tetroxide. The microstructure was characterized as consisting of dispersed protein particles and fibrous networks of protein surrounding variable-sized fat globules. If the fat globules were not thoroughly fixed they were dislodged from the freeze-fractured surfaces leaving vacuoles that could easily be mistaken for air pockets. The study demonstrated that the structure of liver sausage includes both an oil in water emulsion with protein as the emulsifier as well as dense layers of protein or protein-fat colloidal complexes.