Characterization of semi solid food emulsions
Some of our daily food products are emulsion based systems with a soft and spreadable texture like mayonnaise, cream cheese, curd, vegetarian or vegan spreads, and some sausages. For example, fine spreadable liver sausage has a well-defined texture and emulsion system.
The texture and behavior of the food system, while spreading or eating, is as important as its taste. The improvement of the texture is a key target for the food industry. Therefore, it is necessary to understand the emulsion forming process on its molecular level, because this influences the macroscopic behavior like plastic and viscoelastic properties.
Understanding how the emulsion is built by the proteins and emulsifiers and how they influence the texture properties is the main aim of this project.
Typical semi solid emulsions are analyzed with a variety of mechanical and physical-chemical methods, such as rheology and texture analyzer to obtain the macroscopic behavior of the texture like the plasticity and viscous elasticity. Also, the influence of the temperature on the properties of the emulsion is probed by differential scanning calorimetry. To confirm the results from the physical methods, the samples are analyzed optically with coherent anti-stokes Raman scattering microscopy (CARS). With this technique, high resolution images of oil-water-emulsions are accessible, which provides information of the droplet size and distribution.