Decortication

FIG U RE 7.12 Flowchart of the typical dry-milling process of sorghum or millets. Photograph depicts clockwise whole sorghum kernels, decorticated bran, and decorticated sorghum. 

FIGURE 7.13 Abrasive disc decorticator commonly used in sorghum- or millet-milling processes (courtesy of Intermech Engineering Ltd., Morogoro, Tanzania). 

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The long leaf fibers contribute strength to the leaves of certain nonwoody, monocotyledonous plants. They extend longitudinally the hiU length of the leaf and are buried in tissues of a parenchymatous nature. The fibers found nearest the leaf surface are the strongest. The fibers are separated from the pulp tissue by scraping because there is Htde bonding between fiber and pulp this operation is called decortication. Leaf fiber strands are also multiceUed in stmcture. 

The plant is harvested by hand sickle and, after defoUation, is stripped and scraped by hand or machine decorticated. Because of the high gum (xylan and araban) content of up to 35%, retting is not possible. The fibers are separated chemically by boiling in an alkaline solution in open vats or under pressure, then washed, bleached with hypochlorite, neutralized, oiled to facUitate spinning, and dried. 

In the Philippines, the principal suppHer of abaca fiber, the fibrous layer ia the sheath is separated with a knife between the layers, and the strips of fiber-containing layers, called tuxies, are pulled off and cleaned by hand to remove the pulp. In Indonesia and Central America these operations are performed mechanically. Hand- and spiadle-stripped fiber is graded for braids, fine textiles, and cordage decorticated fiber is another class. A cross-sectional view is shown ia Figure 4a. The abaca fiber has a large lumen and the presence of siUcified plates is not unusual. 

Henequen. Agavefourcroydes grows ia Mexico where it was first cultivated by the Mayans ia the Yucatan (Yucatan Sisal). The plant produces for 20—30 years. The lower bottom leaves, which are up to 2 m long and 10—15 cm wide, are cut, machine decorticated, and cleaned. Henequen fibers are white to yellowish red and are inferior to sisal ia strength, cleanliness, texture, and length, the other grading criteria. Henequen is grown for local use ia Cuba (Cuban Sisal) and El Salvador. Twiae, small ropes, coarse mgs, and sacks are made commercially from henequen. 

The fiber is extracted by mechanical decortication. It is whiter, longer, and weaker than sisal fiber. Because of its color it is used ia bleads. 

Phormium. The Phormium tenax plant yields a long, light-colored, hard fiber also known as New Zealand hemp or flax, although it has none of the bast fiber characteristics. The plant is a perennial of the Agavaceae with leaves up to 4 m long and 10 cm wide. The fibers are recovered by mechanical decortication. 

Lanka. The fruits are broken by hand or machine, and the fiber extracted from the broken husks from which the coconut has been removed for copra. The husks are retted ia rivers, and the fiber separated by hand beating with sticks or by a decortication machine. The fibers are washed, dried, and hackled, and used ia upholstery, cordage, fabrics, mats, and bmshes. 

Castor oil may be obtained by cold expression of the decorticated seed. The oil is steamed under vacuum to eliminate odors and coagulate the toxic albumin. Fuller s earth or activated charcoal may be used for further purification. 

Toasted partially defatted cooked cottonseed flour—This product is prepared by delinting and decorticating food-quaUty cottonseed. The meats are screened, aspirated, and roUed moisture is adjusted, the meats heated, and the oil expressed the cooked meats are cooled, ground, and reheated to obtain a product varying in shade from light to dark brown. 

Abrieb, m. rubbings, grindings, dust, fines, abrinden, v.t. peel, strip, scale, bark, decorticate. Abriss, m. outline, sketch, design. 

Entriechung, /. deodorization. entriegeln, v.t. unbar, unblock, release, entrieseln, v.i. trickle away, entrinden, v.t. decorticate, bark, peel. 

Sisal Manual (beating)/microbial retting/decorticator 3-4% of green leaves 900-1200... 

Kozma, R. Russell, J., Jones, T., Marx,N., Davis, J. (1996). The use of multiple linked representations to faeilitate seienee understanding. In S. Vosniadou, R. Glaser, E. DeCorte, H. Mandl (Eds.), International perspectives on the psychologicalfoundations of technology-based learning environments pp. 41-60), Hillsdale, NJ Erlbaum. 

Classic beri-beri, rarely seen in the United States and Europe, except in alcoholism (P4), is endemic in the Far East because of the prevalent diet of decorticated rice (F6). It occurs in two forms wet beri-beri, characterized by edema and cardiovascular symptoms (G6), and dry beri-beri with peripheral neuritis, paralysis, and atrophy of the muscles. Conditions which may predispose to deficiency by increasing thiamine requirements are pregnancy (see section 2.4), and lactation, hyperthyroidism, malignant disease, febrile conditions, increased muscular activity, high carbohydrate diets, and parenteral administration of glucose solutions. A constant supply of thiamine is required for optimal nutrition because storage in the liver and elsewhere is limited. Thiamine is synthesized by bacteria in the intestinal tract of various animals, but this is not a dependable source for man. 

Decorative plating, 9 765-767, 769 Decor paper, 18 129 Decorticated black pepper, 23 162-163 4-Decylaniline (4DA), 14 479-480 n-Decyl chloroformate, molecular formula, 6 291t... 

A major focus of the project has been development of a process to make cowpea meal or flour that could be implemented at the village level. The meal would be a ready-to-use convenience product to which the consumer could simply add water and then proceed to the final steps of preparation. The time-consuming and labor-intensive steps of soaking, decorticating, and grinding would be eliminated. 

The poor performance of finely milled cowpea flours may be due to changes in physical form and structure which occur as a result of milling. Sefa-Dedah and Stanley (10) investigated the relationship of microstructure of cowpeas to water absorption and decortication... 

Research concerning the structure, composition, and usefulness of cucurbit seeds (gourds, melons, squash, etc.) is reviewed. Cytological features are typical of those for oilseeds. Composition-ally, decorticated seeds contain by weight 50% oil and 35% protein. The oil is unsaturated and edible however, certain species contain conju-ated trienoic fatty acids (drying oils). 

The amounts of oil and protein in decorticated seeds are somewhat less varied. Calculations of earlier data from thirteen species show that decorticated seeds contain, by weight, 49.5 + 2.3% oil and 35.0 + 2.4% protein at 95% confidence intervals in the 2 test (1). More recent reports ( 7 24-32) are in substantial agreement with these values. Some studies report oil and protein contents of undecorticated seed (whole seed) or protein content of oil-free meal. Recalculations to decorticated full-fat seeds fit these ranges. 

Decorticated cucurbit seeds contain by weight about 35% protein. Traditionally, seed proteins are classified as globulins and albumins according to their solubility in certain aqueous solvents. Biochemically, oilseed globulins are generally considered storage proteins while albumins are believed to be metabolic (catalytic) proteins. 

Seeds of tea (Camellia sinensis L.) were surface-sterilized in a saturated solution of calcium hypochlorite for 30 min, and soaked for 30 min in running water. The whole seeds, or else seed that had been decorticated, i.e. removed from the hard testae, were sown in moist sea sand and allowed to germinate and grow in dark at 28 °C. 

Morama beans may be eaten when they are still immature green beans, but most of them are eaten as mature beans when the seeds are surrounded by hard woody seed coats, reddish to brownish in color. Therefore, the morama beans need to be decorticated before use. 

A number of studies have been carried out, describing the main chemical composition of the edible part of the decorticated morama bean (T. esculentum) and few samples of T. fassoglense have also been included. A literature survey of the performed proximate analysis is summarized in Table 5.2. 

Tandon SP, Tiwarik P, Rathore YKS. Chemical Constituents of the Decorticated Stem of Plumeria rubra Linn. Proceedings of the National Academy of Sciences, India Section A 1976 46(2) 109-110. 

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