A normalized texture profile analysis approach to evaluate firming kinetics of bread crumbs independent from its initial texture

Firming kinetics of bread crumbs are a major quality-determining factor. In literature, dough variations are often related to crumb firming behaviors. It is hypothesized, that this is often a spurious correlation based on methodological effects due to changes of the crumb void fraction. Thus, the study investigated different initial crumb textures with equal solid materials and a normalized TPA methodology with adapted cylinder probe sizes. The results showed a clear methodological impact of the standard TPA approach. The normalized TPA methodology showed weak or no significant correlations between the crumb void fraction and firmness, the firmness and the firming rate, as well as the void fraction and the firming rate. This proves that mostly changes of the bread volume influence the firming behavior of bread crumbs with equal solid materials. The findings of the current study have to be considered for the interpretation of the firming behavior of bread crumbs.