Dextrins from Wheat Starch

The best dextrins, derived from good potato starch, exhibit a shining reflection, those which appear opaque being usually obtained from wheat or maize starch. 

Manufacture Dextrine is obtained by heating starch from wheat, corn (maize), potato or sweet potato in powder form to 200 270 0 Or 0 15. /... 

Manufacture. Dextrine is obtained by heating starch from wheat, corn (maize), potato or sweet potato in powder form to 200 270°C. Or 0.15-0.3% of nitric acid or 0.4-0.5% hydrochloric acid is added to the starch uniformly, which is well dried and heated to 100 120°C. The former product is called calcinatory dextrine and is brownish the latter is called acid process dextrine and white or yellowish. 

Comparable results were obtained from a structural study of a wheat-starch dextrin. The major fraction from aqueous ethanol solution (37%) was purified by acetylation, and then the deacetylated product was subjected to (a) methylation and hydrolysis, and (6) periodate oxidation, sodium borohydride reduction, and hydrolysis. Both procedures indicated a chain-length of about 8 D-glucose residues. Furthermore, the methylation products were identical with those in Table II, again showing the highly branched structure of the dextrin. 

Processes and products developed to produce industrial materials from renewable resources have been too numerous to record here. For competitive reasons — supply of raw materials and technical and economic considerations — some of the products have varied widely in industrial use. Major U.S. industrial consumption of renewable resources have recently included oils and fats (animal and vegetable) industrial alcohol (wheat, corn, grain sorghum) fibers (cotton lint, flax, hides and skins) paper (forest products) isolated proteins (milk casein, animal glues, soybean, corn) turpentine and rosin (naval stores) and other chemicals (monosodiiim glutamate--wheat starch and dextrin—corn lactose—milk molasses and pulp residues --sugarcane and beet tannin lecithin pectin furfural). 

Spallanzani in 1783 (Sumner and Somers, 1953), the enzymatic hydrolysis of taimin was described by Scheele in 1786 (Tauber, 1949), in 1814 Kirchhoff observed that a glutinous component of wheat is capable of converting starch to sugar and dextrin, and Vogel showed in 1817 that an iirfusion of oats would produce a fermentable sugar from milk (Roberts et a/., 1995). 

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). 

Starch is a natural product from renewable resources, produced during photosynthesis as food reserve for plants and vegetables. It is the second most abundant biomass material in nature. It is found in plant roots, stalks, and crop seeds. The most important industrial starch sources are crops such as corn, wheat, potato, tapioca and rice. By refining these crops several byproducts can be obtained such as oil, bran, gluten, dextrin, sugar (glucose, fructose, HFCS), ethanol (for beverages and bio-fuels) and starch. 

G. Maltodextrin F. malto-dextrines M. are concentrated aqueous solutions of nutritive saccharides, or their dehydrated products, obtained by controlled - hydrolysis of starch and having a DE-value of <20%. [QHioOsln. They are mixtures of - malto-oligosaccharides as well as of - starch polysaccharides with reduced m.w. The ->AGU are linked together by a-1,4- and a-1,6-glucosidic bonds. Production by hydrolysis is performed primarily by the action of thermally stable a-amylases from bacteria on ->com, - wheat, - waxy com, - potato or starches from - cassava, followed by inactivation of the enzyme, purification, concentration and spray-drying. 

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