Flours test baking

Grades of Flour Test Baking Kinds of Flours Enriched Flour Nutritional Value of Wheat Wheat Products and Uses... 

GRADES OF FLOUR TEST BAKING. The highest quality flour is known as patent flour. 

Test baking is one answer to this problem some flour samples that had a good measured composition produce a poor loaf of bread. There are also samples that do not have very promising measured properties... 

Baking tests have to be the ultimate determinant of a flour s suitability for a given purpose. If the flour can be made into a satisfactory product in a test bake then it will work in the bakery. If the test bake is unsatisfactory then no brandishing of analytical results will make the flour fit for the use. 

Bake testing is an important part of any flour testing regime. It remains true that the odd sample of flour that measures well will bake poorly while the converse situation is also true. The reasons for this are usually because there is a problem with the quality of the protein rather than the quantity. It remains much easier to measure the quantity than the quality of proteins present in flour. 

Test-bake loaf volume and dough strain hardening index for two base flours with 1% addition of gluten protein fractions were plotted as a function of the percentage of the total polymeric protein that had been extracted up to each point. The graphs are shown in Figure 7.7 Two... 

Small quantities of wheat are usually milled for test baking. Various flours are checked by different baking procedures according to end use. For hard wheal, test loaves are baked to determine the mixing time and tolerance of doughs, the degree to which the flour will absorb liquid, potential loaf volume, texture, crumb, color, and flavor. For soft wheat, similar determinations are made with test cakes, cookies, or crackers. 

There is an American test for biscuit flour that involves producing standard cookies baked on a standard aluminium plate. The diameter of the finished product is measured. The greater the diameter the higher the score. This test is of course a measure of dough extensibility, which is the crucial property for biscuit flours. 

Triticale flour has been extensively tested in Poland, a country where rye bread is traditional. The best results were obtained by using 90% triticale flour with 10% rye flour. The rye flour was made into a flour brew for 24 hours at 28-29°C. Half the triticale flour was made into a sour dough for 3 hours at 32°C followed by mixing with the rest of the ingredients plus 1.5% of salt on the flour weight. The bread was then scaled and proved for 30 min at 32°C followed by baking at 235-245°C. 

An obvious use of bake testing is to compare the performance of two different batches of flour. In this exercise it is suggested that the control batch is a bread flour while the test should be a non-bread-making soft flour such as an English plain flour. 

For laboratory tests use may be made of a small jacketed metal oven containing heavy mineral oil and coated with asbestos board it is heated by gas and serves to bake loaves of about 150-200 grams prepared by doughing 1 kilo of flour with the required amount of water (about 500 c.c.), 1% of sodium chloride and 20 grams of beer (or pressed) yeast being added and the whole left to rise for 2 hours in an oven at 30-330 C. 

Microscopic Examination —This serves to show if a bread is made from wheaten flour alone or if it contains also extraneous flours. The test is made on the crumb, parts which are less well baked being chosen or, if possible, lumps or nodules of dough such as are often present. The fragments taken are made into a paste with water and the microscopic examination then made. A convenient method, which gives excellent results, is as follows ... 

The ash determined in the above manner furnishes One of the best criteria for deciding what quality of flour has been used in making the bread. If mineral substances or even so-called baking powder were added to the flour, the ash would show an increase in this case, tests 14 and 15 are applied. 

Experiment 125. — Test the following for starch by grinding a small portion of each with water in a mortar, and then adding a few drops of the extract to an exceedingly dilute solution of iodine a) wheat flour, (f) oatmeal, (c) potato, d) rice, e) beans, (/) bread, g) cracker, (//) pepper, (/) baking powder. 

Zeleny, Y. 1947. A simple sedimentation test for estimating the bread-baking and gluten qualities of wheat flour. Cereal Chem. 24, 465 475. 

Figure 7.7 Strain hardening index and bake-test loaf volume as a function of the percentage of polymeric protein extracted from flour of variety Jagger. (Sroan, B. S. 2007. Ph.D. thesis, Kansas State University, Manhattan, KS.)...

Figure 11.1 Bake-test loaf volume versus flour protein percentage for flours from a set of wheat varieties grown at different locations. H. R. W. = Hard Red Winter Wheat H. R. S. = Hard Red Spring Wheat. (Reproduced with permission from Finney, K. R, and Barmore, M. A. 1948. Cereal Chemistry 25 291-312.)...

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... 

The second approach that can be used is to interchange corresponding components between different flours. An example is illustrated in Table 11.1. Flours from two wheat varieties, one of better quality (A) than the other (B), were each separated into three fractions gluten, starch, and solubles. The fractions of each flour were interchanged and bake-test loaf... 

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