Three-dimensional quantitative analysis of bread crumb by X-ray microtomography

Phase-sensitive X-ray microtomography was used as a nondestructive imaging technique for the computerized reconstruction of three-dimensional (3D) images of bread crumb microstructure. After image acquisition, numerical algorithms were used for the slice reconstruction. Successively, 3D images were rendered and quantitatively analyzed. Stereological analyses were performed to determine the void volume fraction and some directionally dependent parameters, such as cell wall number, cell wall thickness, cell wall spacing, and specific surface. Moreover, the favorite orientations of the cell structure and the degree of anisotropy related to the arrangement of the solid phase around the main directions were also determined. Results from statistical analysis suggest that in addition to the void volume fraction, the parameters describing anisotropy or the favorite orientation of cell structure are crucial in understanding the differences observed in crumb architecture. Indeed, the latter parameters can explain more than 50% of whole structural variance existing between bread samples. The ability to reflect the bread crumb compression behavior proved the effectiveness of the microstructural descriptors, as obtained from image analysis, to give representative information on the inner architecture of bread crumb.