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Bakery products - Effect of water

Q: During baking, heat and moisture transport takes place in the dough simultaneously and involves 3 major changes:

Water vaporizes at the cell/dough interface Starch gelatinisation and protein coagulation transforms the viscous dough into a mainly elastic crumb ; these rheological changes limit the cell growth. The structure with gas cells separated by films is transformed into a porous structure with inter-connected pores . Film rupture is associated with the onset of starch gelatinisation.

3 important questions on Bakery products - Effect of water

What are the 4 functions of water, when it is added to flour?

Dissolves soluble molecules
Activates enzymes
Generates the gluten by the binding of the gliadins and the glutenins
Alters the rheological properties of the dough

Where is water present in the bread baking process?

Before baking: the water is absorbed and immobilised by the protein network. The proteins have a higher affinity for the water than the starch granules
During baking: the water moves from the gluten into the starch. Amylose and amylopectin is mobilised and the starch gets gelatinised. Association between water and the starch becomes larger, the water mobility decreases.

During baking, heat and moisture transport takes place in the dough simultaneously and involves 3 major changes:

Water vaporizes at the cell/dough interface
Starch gelatinisation and protein coagulation transforms the viscous dough into a mainly elastic crumb; these rheological changes limit the cell growth.
The structure with gas cells separated by films is transformed into a porous structure with inter-connected pores. Film rupture is associated with the onset of starch gelatinisation.