A approach to the assessing of the physical stability of the emulsion-based foods

A significant number of foods are manufactured in the form of emulsions. However, the resulting macroemulsion is a thermodynamically unstable system. The physical instability associated with processes such as flocculation, coalescing and Ostwald ripening eventually leads to separation of the oil and water phases over time. Predicting this behavior is important for food technology development purposes and especially for reduced oil systems as the most challenging task in terms of system stabilization. In the first approximation according to the Stokes model, the stability of an emulsion is affected by such a microstructural characteristic as the droplet size and the rheological properties of the emulsions. The combination of this approximation with the generalized Casson rheological model for structured liquid systems allows us to propose an approach for estimating the rate of emulsion cremation. The parameters used for calculations are determined from rheology and laser diffraction data. The approach is devoid of empirical variables, since all parameters have a physical meaning on the basis of the kinetic model of destruction-recovery of the structural aggregates of the system.

Calculations were carried out for real food-like emulsions with different nature of the oil phase and different microstructure. The results make it possible to evaluate the physical stability of emulsions, as well as the influence of rheological and microstructural characteristics on the texture of the final product during its shelf life as an important development characteristic.