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Relationship between bread crumb texture and crumb grain uniformity determined by digital image
analysis. M. C. ZGHAL, M. G. Scanlon, and H. D. Sapirstein. Department of Food Science, University
of Manitoba, Winnipeg, MB, R3T 2N2.
The gas retention properties of a dough during proofing is an important
determinant of breadmaking quality. Excessive breakdown of cell walls and gas cell coalescence, associated
with weaker dough for example, leads to coarse and non-uniform crumb grain. Poorer crumb structure also
affects bread texture because of altered crumb mechanical properties. This study examined the influence of
crumb grain uniformity on fresh bread texture. Bread was prepared using a short time process and four
spring wheat flours of varying strength. Proof time was varied to manipulate crumb grain. In addition to the
standard crumb grain measurements by digital imaging, distributions of cell size and cell wall thickness
were determined. The tensile properties of crumb specimens were measured using a TA.XT2 texture
analyzer. Crumb density and texture were significantly correlated to mean cell area, but not to mean cell
wall thickness. Increasing proof time significantly broadened the distributions of cell size and cell wall
thickness. Results indicated that increasing dispersion in the distribution of cell size and cell wall thickness
significantly decreased crumb stiffness and strength. Gluten protein quality, presumably by its influence on
gas cell coalescence, also appears to be an important factor affecting the texture of fresh bread crumb.
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