Bread crust color

Bread and buns. 1 to 3% defatted SF (on flour basis) increases absorption of water by one pound for each pound of soy flour and improves crumb body, resilience, crust color (from sugars), and toasting characteristics. 

Pan bread formulations usually contain small quantities of nonfat dried milk (1% to 3.5% based on flour weight). The milk slightly increases water absorption, and improves crust color (golden color) and flavor. It is noteworthy that yeast is not capable of breaking down lactose and therefore this disaccharide remains unaltered until the baking process, where it contributes to crumb color. Milk also improves nutritional value because its protein complements the amino acid pattern of wheat proteins and supplies important amounts of calcium, magnesium, and other essential nutrients (Doerry 1995, Kulp and Ponte 2000, Stauffer 1990). 

Since it is precisely at the surface of roasting meat that water concentrations are lowest and temperatures are highest, it is at the meat surface that the flavor and color generating activity during roasting is most prominent. This situation is analogous to the formation of crust and aroma in bread and other baked cereal products. The same facts also account for the significant difference between roasted and boiled meats. 

These nonenzymatic reactions are responsible for numerous changes on food properties and may impair food safety. Although these reactions are of great importance in the production of aroma, taste and color, they are often accompanied by a reduction of the nutritive value of different foods and by the formation of toxic compounds harmful for human health (Ledl and Schleicher, 1990). Results of nonenzymatic browning can be either desirable or undesirable. The brown crust formation on bread is desirable the brown discoloration of evaporated and sterilized milk is undesirable. For products in which the browning reaction is favorable, the resulting color and flavor characteristics are generally experienced as pleasant. In other products, color and flavor may become quite unpleasant. 

When a food is kept, the concentration of solutes, which may at first be uneven, becomes (slowly) evened out. This may be of considerable importance for the eating quality if it concerns flavor components see the introduction to Chapter 9. Likewise, color substances may become evenly distributed e.g., moving from the fruit to the surrounding yoghurt and so may water e.g., from the inside of the bread to its crust, by which the crust loses its crispness. 

Starch degrades to dextrins, mono- and disaccharides at the relatively high temperatures to which the outer part of the dough is exposed. Caramelization and nonenzymatic browning reactions also occur, providing the sweetness and color of the crust. The thickness of the crust is dependent on temperature and baking time (Table 15.51) and type of baked product (Table 15.54). The composition of some types of bread is presented in Table 15.55. 

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