Rheological properties of short doughs at small deformation

The rheological properties of short doughs of various composition were determined in dynamic shear experiments at small deformation. Regardless of composition, the linear region was very limited; beyond it significant structure breakdown occurred. Furthermore, an increase in storage modulus was invariably observed in time-sweep experiments. In addition to oscillatory experiments, conductimetry was used to evaluate short doughs with different fat types and fat content. Short doughs showed differences in mechanical spectra and in conductivity, depending on fat content and fat type. These results are considered in terms of the structure of short doughs. It is concluded that short doughs are bicontinuous systems; reducing the fat content or changing its rheological properties relative to those of the non-fat phase results in fat-dispersed systems. At small deformation, the rheological properties of the non-fat phase are largely determined by flour/starch particles. (C) 1997 Academic Press Limited.