Wheat flour dough

Sour dough Wheat flour Lactobacillae, Saccharomyces cerevisiae... 

Certain cereal grains, especiaUy wheat and rye, contain hemicelluloselike arabinoxylans [9040-27-1], commonly caUed pentosans. Wheat flour pentosans are divided into two types water-soluble and water-insoluble arabinoxylans, which respectively constitute - 1.1 1.6% and 0.4—0.7% of the total flour. These polysaccharides have functional roles in dough development and baking performance. The water-soluble wheat-flour arabinoxylans consist of a (1 — 4)-linked chain of P-D-xylopyranosyl units substituted at 0-2 and/or 0-3 with single-unit a-L-arabinofuranosyl units. Preparations from each source consist of a family of molecules of various molecular weights and xyl ara ratios. 

A neutral bacterial endoprotease can be used to weaken the gluten in wheat flour, if necessary, or to provide the plastic properties required ia a dough used for biscuits. 

Wafer Flour. Wafer flour is a type of biscuit flour with the same basic specification of low protein soft wheat flour with a low starch damage. Once again the required dough property is extensibility. The only differences are that if the protein is too low the wafer will be too soft to handle, and if the protein is too high the wafer will be too hard. The other important property is a resistance to gluten separation. Wafer flours are likely to be brown. 

Types of Rye Bread. The usual descriptions are logical. Rye bread is bread made solely from rye flour, rye/wheat bread contains a minimum of 50% of rye flour while wheat/rye bread contains not less than 50% wheat flour with not less than 10% of rye flour. Some recipes for San Francisco sour dough bread have a proportion of rye flour. No doubt, originally, the prospectors used what ever was available. 

Pretzels are made from a very stiff dough that is made from a low protein soft wheat flour, e.g. one made from a soft white winter wheat. The water level would be only 38 42%, with 0.25% yeast and 1% shortening, 1 % salt and 1 % dry malt. The dough would be mixed in a Z blade mixer and then left to prove for up to 4 hours. 

Nielsen et al. (39) used pea flour and pea protein concentrate, both cooked and raw, in noodles and spaghetti. The pasta was made from composite flours prepared by blending 33% pea flour with 67% wheat flour or 20% pea concentrate with 80% wheat flour. Protein content of the fortified noodles was approximately one-third higher than the wheat flour noodles. Addition of pea flour reduced the cooking time, but resulted in a softer product and lower yield than the wheat pastas. Precooking the pea flour improved flavor and decreased noodle dough stickiness, but the texture and yield of the cooked pasta was still less than that of wheat products. 

Unheated pea flours are also effective in bleaching and improvement of doughs (37,31). Mixing times are shorter with pea-wheat flour combinations, and mixing tolerance is increased. 

Figure 1. SEM o/ wheat flour dough after mixing (4)...

Figure 9. Mixograms of doughs from flours prepared from three varieties of wheats varying in dough performance (21, 22)...

Verma and McCalla ( ) studied the action of pepsin, papain and a commercial fungal protease on wheat gluten. All enzymes acted effectively on dispersed gluten however, the action of different enzymes produced different types of digestion products. Depending upon desired handling characteristics of bread doughs prepared from treated wheat flour, various types of protease treatments can be selected. 

Beuchat (60) investigated the performance of enzyme-hydrolyzed defatted peanut flour in a cookie formula. Flour slurries were treated with pepsin at pH 2.0, bromelain at pH 4.5, and trypsin at pH 7.6. After readjustment to pH 6.9, materials were freeze-dried, pulverized (60-mesh), and then substituted for wheat flour at 5, 15, and 25%. Adjustment of peanut flour to pH 2.0, as well as treatment with pepsin at this pH, greatly improved the handling characteristics of dough in which these flours were incorporated. Use of peanut flours treated at pH 4.5, with or without bromelain, and at pH 7.6, with or without trypsin, improved handling properties of cookie dough. These doughs did not tend to crumble... 

Bagley, E.B., Christianson, D.D., and Martindale, J. A. 1988. Uniaxial compression of a hard wheat flour dough Data analysis using the upper con-vected Maxwell model. J. Texture Studies 19 289-305. 

K. Mani, A. Eliasson, P. Dejmek and C. Tragardh, The Viscosity of Wheat Flour Doughs - the Problem of Slip, Anal. Trans. Nordic Rheol. Soc., 2 35-37 (1994). 

J.A. Menjivar, E.N. Chang and L. Maciel, Extrudate Swell Behaviour of Wheat Flour Doughs, in "Theoretical and Applied Rheology", P.Moldenaers and R. Kennings (eds.), Elsevier Science B.V., 1992, pp. 714-716. 

B.J. Dobraszezyk, Strain Hardening in Biaxial Extension of Wheat Flour Doughs, presented at the 2nd Int. Meeting on Extensional and Shear Flow of Polymer Fluids, St. Andrews, Scotland, June 19-22,1994. 

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