Molecular and material science approaches in bread-making: insights in the impact of bran and opportunities for enzymatic functionalization

The production of foods rich in dietary fiber represents one of the most important driving forces in the development of innovative cereal-based products. However, wheat bread enrichment with high-fiber material generally results in altered rheological and baking properties in respect to products derived from refined flour. In this paper, a molecular and material science approach is used to describe the technological impact of bran in wheat dough. In particular, focus is given on (i) gluten solvation and structural arrangements in presence of bran, (ii) thermodynamic principles describing the effect of bran on starch gelatinization during baking and (iii) the impact on the textural properties of the bread crumb considered as a multi-phase mixed system. Following on the physical mechanisms described, enzymatic modifications are proposed to optimize the techno-functionality of bran in bakery applications.