Wheat starch color

Wheat starch possesses a unique combination of properties that is important to its utilization in various food and industrial products. Those properties are related to its color, purity, flavor, paste viscosity, paste clarity, paste texture and gel strength.27 28,311-315... 

Water washed, salt solution washed, cold solvent washed and sieved wheat starches did not improve filterability and final color of glucose syrups compared to those of well washed large granule wheat and com starches.561 When using a well washed, large granule wheat starch fraction, the ease of processing and final syrup quality are similar in most respects to that of corn syrups. 

It is estimated that 60-70% of the caloric intake by humans comes from starch. As such, starch has been of great importance in the evolution of organisms and especially for humans, where it also has had a role in the evolution of culture. Besides being used as an essential food, wheat starch was used to give body and the ability to hold ink to papyrus, a thin bark that was the earliest material used for writing ( 4000 B.C.), especially in Egypt. When paper was developed in China, around 100 A.D., starch was also used to give body to the paper and to hold ink on the paper and it continues today to be used to size paper. The Romans ( 100 B.C.) used starch to whiten cloth and to powder hair, and about 300 A.D., it was widely used to stiffen cloth and was often mixed with dyes to color the cloth. Colored starches (especially yellow and red) were also used as cosmetics. 

Pentosans. These compounds are polysaccharides which may he considered as anhydrides of pentose sugars, after the manner of the hexosans. sucrose, starch, from glucose, fructose. When pentosans or pentoses are heated with hydrochloric ot sulfuric acid, furfural C fljO CHO is formed, and addition of aniline produces a red color. Pentosans are present in gummy carbohydrates, in bran of wheat seed, and in woods. 

This results from the transformation of starch by means of heat or by the action of dilute acid or diastase. It is prepared principally from potato, wheat or maize starch and rarely from rice or other exotic starches. Many varieties of dextrin, made in diverse ways, are sold under different names. It occurs as a fine powder, either wliite, dirty white, yellowish or light brown as granules, similar in appearance to gum arabic and as a thick syrup, more or less highly coloured and opaque. In general dextrin has a special odour and taste, which are particularly marked in the pulverulent varieties. It is soluble in water, but insoluble in alcohol. Its solution is strongly dextro-rotatory the value of [a]D varies from 173° to 2250,but is mostly about 200°. With iodine different dextrins give bluish violet to brownish red colorations (the colour is observed by adding the iodine solution drop by drop if the mass is mixed after the first drops are added, the colour disappears). 

Wheat <Dairy products> starch, protein, moisture, ash, hardness, damaged starch, a-amylase activity, amino add, color value, ratio of contaminated bran, bread making quality, discrimination of cultivar... 

Glidine, a commercial diabetic food which is prepared from wheat flour and contains over go per cent of protein, may be used as a satisfactory source of glutamic acid. If this is used, it is not necessary to wash in order to remove the starch. From 1130 g. of this material, by hydrolyzing with 2500 cc. of concentrated hydrochloric acid and working up as before, 275-285 g. of glutamic acid hydrochloride may be obtained. Usually, the product from glidine is more difficult to decolorize. It has been found that an ether extraction of the hydrolysis mixture, after removal of the melanin, improves the color of the final product. 

As with iodine, starch forms an inclusion complex with bromine vapor.205 Depending on the starch variety, different colors are developed by the complex. Maize and wheat produce an ochre color, rice produces a light-buff color, potato and sago develop a pale-yellow color, and cassava forms a cream color.69 Iodine cyanide (and bromine)-amylose complexes are brown-black and dark brown, respectively.206 The adsorption of chlorine and iodine proceeds according to the Freundlich isotherm. A discontinuity on the Freundlich isotherm plot is reported, which possibly results from the swelling of starch granules454... 

Other organic fiber products which are mostly used in foods as dietary ballast additives are made from wheat, oats, tomato, apples, and citrus. Such dietary fibers are non-starch polysaccharides obtained from cell walls only, which can not be broken down by the digestive enzymes of the human organism and, therefore, constitute inert ballast materials. Color, taste, and odor relate to the fiber source. Unlike cereal brans or dietary fibers derived from, for example, sugar beets, which are often rejected by consumers because of their specific taste, wheat, oat, tomato, apple, and citrus fibers offer physiological properties that are much more readily accepted. 

Soy sauce is made only from soybean, wheat, and salt. The protein in soybean changes to components that produce flavor and color unique to soy sauce by microorganisms. Wheat, rich in starch, is mainly used to create the aroma unique to soy sauce. At first, soybeans are steamed. Wheat is roasted and ground into small pieces. After that, the soybeans and wheat are mixed together. 

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