Steady shear flow and dynamic rheology of the emulsions containing ultrasound-assisted extracted Plantago major seed gum

The rheological properties of emulsions containing ultrasound-assisted extracted Plantago major seed gum with different concentrations (0.3, 0.5 and 1% w/v) were discussed in this paper. The results of steady shear flow experiments were categorized in three main groups: Shear rate – shear stress (fitted well with Herschel - Bulkley model), apparent viscosity – shear rate (fitted well with Carraeu model) and shear stress – time relationships (fitted well with Tiu - Bugar model). Models were selected due to their R2 and RMSE values. The dynamic rheology experiment results including strain and frequency sweep demonstrated that all emulsions showed gel-like behavior which is resulted from more stable interactions and chains in the structure. Cox – Merz rule was applied to investigate the relationship between complex viscosity (η*) as a function of frequency and apparent viscosity (ηa) as a function of shear rate in which the results considered that in all samples the complex viscosity was higher than apparent viscosity. Therefore, the PMS gum based emulsions did not obey this rule.