Starch Separation Research Articles

A New Hydrocyclone Process for the Separation of Starch and Gluten from Wheat Flour

AbstractA batter of wheat flour and recirculation water is directly introduced into a hydrocyclone system in which the prime starch is separated and washed out in countercurrent with fresh water. Agglomeration of the gluten takes place spontaneously in the hydrocyclones. The gluten agglomerates come free in the overflow of the system and can be separated easily by screening. The working of the hydrocyclones is not influenced by the presence of the gluten agglomerates. The total waste water stream is approx. 2 m3 per t of processed wheat flour.

DENSITY SEPARATION OF PROTEIN AND CARBOHYDRATES IN A NONAQUEOUS SOLVENT SYSTEM

ABSTRACTThe proteins and carbohydrates in wheat flour, soybeans, green peas and dried acid whey were separated on the basis of density in a non‐aqueous solvent system. By dispersing finely milled flour in solvent ranging in density from 1.3–1.5 a protein rich fraction can be readily separated from a carbohydrate‐rich fraction by centrifugation. The protein fraction from wheat flour contained from 58–81% protein while the carbohydrate fraction contained only from 0.4–3.9% protein. After separation and recombination the baking quality of the wheat flour showed little modification. Similar separations were obtained for the other protein sources tested. Trichlorofluoromethane (Freon 11) mixed with ethanol, acetone, ethyl acetate, or hexane were evaluated as solvent systems; the ethanol‐containing mixtures gave significantly better separations than the other solvent systems Acetic acid and formic acid were not effective for improving separation while addition of sodium hypochlorite did improve the separation of protein and starch.

Integrated Starch Plant for Alternative Processing of Maize and Potatoes

AbstractThe emphasis of this paper is on the starch plant, in order to indicate how a great portion of the wet‐milling equipment and all the dryers are used for two raw materials. The flowsheet for maize is the standard Dorr Oliver flowsheet. The primary separation of starch and gluten takes place in a merco separator. The same machine is applied for the separation of the effluent from the crude potato starch milk. The maize gluten concentration takes place in a gluten concentrator. The same machine is used for the recovery of the starch from the overflow of the first stage of starch washing when producing potato starch. The 7‐stage fibre washing system is used for both maize starch and potato starch. The starch washing systems is used for both starches too.

Verbesserte Flutenrinnen‐Versuchsanlage für die Stärke‐Klebertrennung von Mais

AbstractImproved Starch Settling Tables Test Plant for the Laboratory Separation of Starch and Gluten of Maize. An apparatus for separation of starch and gluten as part of the laboratory determination of the processing value of maize for wetmilling is described. The apparatus consists of a mobile chassis and a starch settling tables‐plant with collimating equipment which guarantees fast readiness for operation and precise adjustment of the incline of the settling tables and thus high reproducibility of test results.

Grafting of poly (methyl methacrylate) to granular corn starch

AbstractGraft copolymers were prepared by the radical‐initiated polymerization of methyl methacrylate in aqueous slurries of granular corn starch. High conversions of monomer were realized, giving products which were readily recovered by filtration. The products were free‐flowing, white powders, which by microscopic examination looked much like granular starch. Grafting was demonstrated by extracting the granular products with ethylene dichloride, which in most instances removed only a minor part of the poly(methyl methacrylate). When azoisobutyronitrile was used for initiation, a high conversion of monomer resulted, but about 90% of the polymer was extractable with ethylene dichloride. Further evidence for grafting was obtained by extraction of predissolved product, prepared by dissolving the granular product in dimethyl sulfoxide, to destroy the structure of the starch granules, and precipitating with alcohol. The fractions soluble in ethylene dichloride contained significant amounts of carbohydrate. Similar treatment of product prepared with azoisobutyronitrile initiation or of physical blends of starch and poly(methyl methacrylate) gave much more efficient separation of starch from PMMA. Failure to obtain grafting with AIBN initiation suggests that grafting occurs mainly as a result of attack on starch by radicals generated by the reaction of hydrogen peroxide or organic hydroperoxide with ferrous iron. Acid hydrolysis of the products removed the starch. The PMMA so recovered typically had viscosity‐average molecular weights of the order of 106, which suggests the grafts contained very long branch chains of PMMA attached at very infrequent intervals.

Separation and Purification of Starch from Chufa Nut Tubers (Cyperus esculentus)

Separation and Purification of Starch from Chufa Nut Tubers (Cyperus esculentus)

PRODUCTION AND PROPERTIES OF 2,3-BUTANEDIOL: IX. THE EFFECT OF VARIOUS NUTRIENT MATERIALS ON THE FERMENTATION OF STARCH BY AEROBACILLUS POLYMYXA

Wheat starch is a poor medium for fermentation by Aerobacillus polymyxa. The solubles recovered from the separation of starch and gluten in patent flour enhance the fermentation but not as effectively as the similar fraction from whole wheat flour. Addition of supplements is necessary for a satisfactory yield of products in a reasonable length of time. Wheat gluten has no stimulatory effect but bran and shorts are both effective, the latter being slightly superior. An 8% starch medium fortified with the solubles from whole wheat required a 2.5% supplement of shorts to bring fermentation by A. polymyxa to 90% completeness in 72 hr.Of the various supplements tested, a 1% addition of malt sprouts proved to be the most effective, fermentation being 90% complete in 72 hr. Shorts, bran, Cerogras (dehydrated young oats), alfalfa, soya beans, yeast extract, and corn-steep liquor follow in order of decreasing effectiveness.The solubles from whole wheat when ashed have no beneficial effects on the fermentation of starch by A. polymyxa.

SEPARATION OF STARCH AND GLUTEN: II. EFFECTS OF PROCESSING FACTORS ON THE STARCH CONTENT OF WHEAT GLUTEN

The effects of dough mixing time, dough conditioning, and washing temperature and time upon the mechanical separation of starch and gluten were studied in duplicated factorial experiments in which straight and clear grades of hard red spring wheat flour were employed. Glutens of low starch content were obtained over a considerable range of processing conditions, washing time being the factor of greatest importance. After comparable washing periods of 45, 60, and 90 min., average starch contents were 7.3, 2.4, and 0.8% respectively. The practicability of employing water recirculation in the batch preparation of practically starch-free gluten has also been demonstrated.