Gas cell opening in bread dough during baking

Background: This literature review describes the evolution during baking of the three main components in dough (starch, proteins, and the aqueous phase) in order to understand what causes gas cells to open. To date, most of the literature has focused on the role played by proteins, gluten having received most attention in the last decades (strain hardening properties, ability to stretch without rupturing etc.). The possible role of a liquid lamella has more recently been proposed. While a number of articles directly evidence its existence, indirect results also provide proof of its presence. The role of starch in the mechanisms of gas cell stabilization/destabilization has been little considered. The multiple actions of starch described in this review may offer an explanation for this. Scope and approach: The authors have set out to consider all phases and to understand how they may interact during baking in such a way as to lead eventually to gas cell wall rupture. Key findings and conclusions: The four most likely situations are presented and discussed: gluten with poor ability to stretch: rupture occurs too early during baking. gluten with poor ability to stretch but assisted by a liquid lamella: rupture is delayed; extent of delay is dependent on starch's sorption of water. gluten with good ability to stretch, starch granules soften early during baking but do not fuse (ideal situation): structure opens late in baking when loaf is able to sustain its own weight. too many fusing starch granules: gas cell walls fail to rupture and loaf shrinks during cooling.