Baking wheat, lipid

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-... 

The lipids are preferentially stored in the germ which, in the case of com and wheat, serves as a source for oil production (cf. 14.3.2.2.4). Lipids are stored to a smaller extent in the aleurone layer. Cereal lipids do not differ significantly in their fatty acid composition (Table 15.31). Linoleic acid always predominates. Close attention has been given to wheat lipids since they greatly influence baking quality ttnd they have therefore been studied thoroughly. 

In the food industry, lipases are used in lipid modification processes. In these processes the texture, digestibility, or physical properties of natural lipids are modified by lipase-catalyzed transesterification reactions with lipids other than the original fatty acids. In the baking industry, lipases are used to influence the quality of bread through modification of the wheat flour lipids. Finally lipases are used for flavor enhancement of cheese in the dairy industry. 

An example is illustrated in Figure 11.3 (cf. Figure 7.10 in Chapter 7) for the effect of varying the natural lipid level of a wheat flour on bread loaf volume in an optimized lean formula baking test. The behavior is unusual. The nonstarch flour lipid has been solvent-extracted using chloroform and added back incrementally to the defatted flour. Small additions of lipid decrease loaf volume imtil a minimum is reached at a lipid... 

Fig. 15.20. The effect of free nonstarch lipids on the baking quality of defatted wheat flour (according to Morrison, 1976). — Lipids (total), — o-o- nonpolar lipids, polar lipids...

---