Studies on Rheology of White Bread (Part 1)

Compressibility and Elastic Moduli of Bread Crumbs

Abstract

An investigation for mechanical properties of white bread has been performed by using an uniaxial compression testing machine developed, and the compressibility as well as elastic properties of the crumb have been discussed from the rheological point of view.
For the range of deformation rates up to 25%, a force-deformation curve was found to consist of the four stages which were defined as (1) initial toe, (2) proportional stage, (3) transition and (4) breaking regions, respectively. The experimental results indicated that the structure and mechanical strength of the crumb changed by directions showing its anisotropy. The values for proportional limit, equivalent Young's moduli and Poisson's ratios of elasticity were also determined within the proportional stage at which the clumb could be assumed to be an elastic body.
The results on breaking behavior and viscoelasticity will be reported in subsequent studies.