Starch—gluten separation

Chiang, W.C. and Lee, A. 1995. New Developments of Improving Starch-Gluten Separation . Dorr-... 

Chiang WC, Lee A New Developments for Improving Starch-Gluten Separation. Milford, CT Dorr-Oliver 1995. 

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. 

The separation of the germ, gluten and starch is accomplished in the wet process by the reels. These are long open cylinders covered with perforated copper or silk depending upon the work to be done by the reel. The grams are separated by the coarse copper reels. The starch is separated from the coarse and fine feed, by file coarse feed reels, the No. 9, the No. 12 and the No. 17 silk reels. Sometimes even No. 20 silk reels are used. 

Recently, much attention has been given to the production of liquid sweeteners as an alternative to cane sugar using inexpensive starch-containing natural materials as the primary feed stock. This situation exists in the United States as this country is not self sufficient in the production of cane, but must rely heavily on importation mainly from South America and the Caribbean. The main source of sta rch in the United States comes from corn (Zea mays) and the liquid sweetener commercially produced from this material is called high fructose corn syrup (HFCS). The current method of production of HFCS is via wet milling which exploits the physical properties of the whole corn constituents (oil, starch, gluten, and fiber) for their separation coupled with enzymatic hydrolysis of the starch fraction to monosaccharides. 

Germ separation Fiber separation Gluten separation Starch washing... 

The total A-starch is separated as a concentrate, while the gluten obtains its typical structure and is discharged with the B-starch via the medium fraction. The %htweight constituents of flour such as pentosane form the third phase. Following on from fine fiber screening, three-phase nozzle separators perform the task of separating the A-starch and recovering the A-starch left in the B-starch. The A-starch is washed by hydrocyclones. Two-phase decanters ensure that the two starch fractions are dewatered and process water is treated in a clarifier. 

Starch is primarily derived from corn (maize). The cleaned grains are soaked to soften them, then mcchatiicaliy rendered to liberate the corn germ, which is the oil containing component. The remainder of the kernel contains starch, gluten and fibre, which are progressively. separated, and the starch is then classified. The decanter has some part in both the separation and classification stages. 

After the germ has been removed, the rest of the corn kernel, containing starch, gluten, and bran (the outer hull of the kernel) is screened, and the bran is removed. The remaining mixture of starch and gluten is separated by centrifugal action. The starch portion is either dried, or modified and dried, and sold to the food, paper, and textile industries, or is further converted into various sweeteners. 

Corn wet-milling Industrial process in which yellow dent corns are steeped in a solution containing sulfur dioxide and naturally occurring Lactobacillus and then wet-milled in order to release the starch granules and protein or gluten, which are separated due to their differences in density. The process yields prime starch, gluten, germ, pericarp, and solids of the steep liquor. 

Apphcations include ka olin clay dewatering, separation of fish oils from press Hquor, starch and gluten concentration, clarification of wet-process phosphoric acid, tar sands, and concentrations of yeast, bacteria, and fungi from growth media in protein synthesis (14). 

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