The effect of storage time on textural and crumb grain characteristics of sourdough wheat bread

Texture and crumb grain characteristics are two major quality attributes of bread products. Instrumental methods for measuring textural properties are widely used as tools for the objective measurement of texture properties. Digital image analysis is a relatively new, non-destructive technique that can be used for the evaluation of crumb grain structure. During this study the effects of sourdough on texture and crumb grain characteristics of wheat bread were determined; the effects of storage on these characteristics were measured and possible relationships between texture and structural characteristics were investigated. Sourdough wheat breads with 20 or 40% sourdough were produced according to a standard procedure. Bread with no added sourdough was used as a standard. Crumb texture profile analysis and crust penetration were performed 4, 26, 50 and 74 h after baking. The crumb grain characteristics of the breads were evaluated using an in-house digital image analysis system. Wheat bread with 20% sourdough showed reduced crumb firmness and slower firming over time. Digital image analysis revealed increased crumb shrinkage in both sourdough breads. Possible relationships between crumb shrinkage and crumb firmness, chewiness and resilience were established.