The complex shear modulus of dough over a wide frequency range
Résumé
It is shown from small strain shear rheometry and low intensity ultrasonic shear wave measurements that power law behaviour describes the frequency dependence of the complex shear modulus of dough made from a strong North American breadmaking wheat flour. This is the first characterization of the linear viscoelastic behaviour over such a wide frequency range (more than eight decades). Standard rheometry was used to determine shear moduli at low frequencies while an inclined incidence wave reflection technique was used to measure the complex shear modulus in the 105 Hz region. The ultrasonic data demonstrate that previous descriptions of the constitutive properties of this rheologically complex material do not incorporate a sufficiently broad range of relaxation times to comprehensively model the rheology of dough at all frequencies. Modeling the dough as a power-law gel material permitted its linear viscoelastic response to be described well over the full frequency range.
