Dough lipids

It is also important to remember that wheat gluten and dough are complex materials, consisting not only of protein and water, but also starch-, lipid-, water- and salt-soluble proteins and smaller carbohydrates, and so on. The properties of these materials and their interactions with the gluten proteins are poorly understood but can be expected to also influence the viscoelastic properties. The challenge therefore is to understand gluten structure at the molecular level and how this structure interacts... 

Li, W., Dobraszczyk, B.J., and Wilde, P.J. (2004). Surface properties and locations of gluten proteins and lipids revealed using confocal scanning laser microscopy in bread dough,... 

In short, the kneading of dough introduces air cells, and during fermentation the carbon dioxide will increase the volume of these cells until a foam is obtained. In the oven the foam opens to give a pore system and the structure is "fixed" due to starch gelatinisation. Tlte process involves different steps where proteins and lipids compete at the interface, which we will consider in more detail. 

The three dimensional form can be best visualised as a swiss roll, where jam represents the water and the sponge is the lipid layer with the polar head interacting with the water. These structures are important in the stabilisation of doughs and batters and in particular in promoting foam stabilisation at the air / water interface. 

Certain polar lipids, notably stearoyl-2 lactylate, have been shown to be efficient dough improvers and even at very low concentrations result in increased mixing tolerance, increased loaf volume, finer grain, and softer crumb in breads (Table VII) (46, 47). They have become particularly useful in improving the functional quality of baked wheat-... 

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