Application of Rheological Modeling in Food Emulsions

Various scaling methods such as relative viscosity, Peclet and Reynolds scaling were used to find the best scaling law. Scaling and modeling of the flow curves of various model emulsions consist of Tragacanth Gum (TG) (0.5, 1 % wt), Oleic acid (5, 10% v/v) and WPI (2, 4 % wt) were investigated and the best models were selected.

As these emulsions are non-Newtonian, they do not obey the usual, simple scaling laws. When the apparent viscosity is reduced to relative viscosity of the medium at zero shear rate, a distinct reduced flow curve is obtained, regardless of TG, oleic acid and WPI concentrations. This will lead to a technique of simplifying complex non-Newtonian flow curves and therefore predicting the rheological flow curves and fluid mechanics when different modifiers are added to food emulsions.

The flow behavior of all samples was successfully modeled with Cross, power law and Ellis models and power law model was found as the better model to describe the flow behavior of dispersions. Results showed that both G' and G'' increased with TG, oleic acid and WPI concentrations with pronounce effect of TG content.