Wheat chemical composition

Wheat offals vary so much in size of particle and in chemical composition in different districts that it is almost impossible to give average data concerning them.1... 

The extraction of two typical agricultural products from environmental matrices were chosen as examples for the operation of this system. Diuron, a phenylmethylurea, was freshly spiked onto Tama soil. This soil was characterized and shown to have 3.1% organic material and 14 % clay fraction. In addition, a phenyl metabolite of NUSTAR, a systemic fungicide, on wheat previously unextractable by SFE was extracted. The wheat sample was not classified for its chemical composition. Both samples were treated with radiolabeled compounds (E. I. du Pont de Nemours and Company, Du Pont Agricultural Products, Wilmington, DE) and extraction results are from liquid scintillation counting of the sample extract. Chromatographic evaluation of the Diuron from soil extracts has previously been published (2). 

The chemical composition of isolated oat starch is given in Table 15.1. When an oat-flour slurry is centrifuged, the bottom layer is the prime starch. This starch can be purified with repeated washings, and a starch with a protein content of 0.44-0.6% and a lipid content of 0.67-1.11% (dry basis) can be obtained.10,27 The moisture, ash and nitrogen contents are similar to those of wheat, whereas the lipid content is higher than that of wheat, and the amylose content is lower.15... 

The samples used in the study comprised various biomasses and a selection of Danish straws. The analyses of the fiiels used in the study are presented in Tables 1 and 3, and the chemical composition of ash, together with a summary of the thermobalance sintering tests, in Tables 2 and 4. The Danish wheat straw qualities were selected on the basis of growth site, fertilising and weathering conditions [9],... 

Fig. 4 The composition measured for particles of bottom, 2nd cyclone ash and hot filter dust samples taken irom a CFB test run of wheat straw. For comparison, the chemical composition of ash of feedstock straw is shown as red bars at the right ends of the diagrams (note for better visualisation, the array of the graphs in bottom ash diagram deviates from that of the other diagrams).

Insect pest infestation causes losses in quantity and quality of food commodities and changes in chemical composition, affecting the nutritive value of the produce (Howe, 1965 Scott, 1991 Swaminathan, 1977). Insect activity also leads to contamination of the produce (Table II). The flour beetles (Tribolium spp.) contaminate foodstuffs with their secretions, which contain 2-ethyl 1,4-benzoquinone and 2-methyl-1,4-benzoquinone. T. castaneum quinone secretions not only impart off-odors to food commodities but are also considered to cause liver and spleen tumors in mice (El-Mofty et al., 1992). However, Hodges et al. (1996) demonstrated that unlike in wheat flour, the accumulation of quinone secretions of T. castaneum adults in rice was negligible at less than 1 ppm, and hence, they claimed that T. castaneum infestation in rice is not likely to be a health risk. Males of R. dominica secrete aggregation pheromones (dominicalures) that contribute to the characteristic sweetish or musty odor in grain infested with R. dominica (Khorramshahi and Burkholder, 1981). However, Seitz and Sauer (1996)... 

Chemical composition Rhyzopertha dominica Wheat Saxena and Singh (1994)... 

Saxena, A. and Singh, Y.P. 1994. Fluctuation of chemical composition in wheat varieties damaged by Rhizopertha dominica Fabr. Bull. Grain Technol. 32, 163-167. 

Chemical Composition of Extracted Hemicellulose of Wheat Straw... 

However, to characterize the solubilized hemicelluloses of the wheat-straw samples, the four extracted fiactions obtained and the commercial hemieellulose of birch wood (Sigma ) were hydrolyzed to determine their sugar constituents, and the results are given in Table 2. The major monosaccharide obtained was xylose of birch wood (48.1%), indicating the presence of a xylan. In the hemicelluloses of wheat straw, the major monosaccharide was arabinose (36.5%), indicating the presence of an arabinoxylan. However, these sugar concentrations were very low which can likely be due to the methodology used to determined the chemical composition of the hemieellulose extracted from wheat straw. 

Concerning the toxicity of different flours Glabau says In using different flours, the baker often receives a flour which will not ripen as readily as others in the fermentation which he has used, and he terms such flour hard, or harsh then again he will get a flour which acts just the reverse. In some instances it will ripen in one-fourth less time. The dough will also be softer and have a tendency to run. Such effects are due to the physical constitution and chemical composition of the protein constituents of wheat flour. 

Purified plant fibers for dietary purposes are combinations of cellulose, lignin, hemicellulose, gums and pectinaceous substances that exert chemical and physical actions in the gastrointestinal tract. Dietary fiber complexes such as wheat bran contain not only the fiber components but also other organic compounds that contribute to nutrition. In comparison to wheat bran, the deproteinized and decolorized fiber complexes of tobacco and alfalfa have favorable chemical composition as dietary fibers. Their low concentrations in starch and lipids... 

The differences in for wheat can be attributed to a difference in the chemical composition between wheat types, which affect the EMC characteristics on which the calculation of is based. 

The production of lecithin from soybeans is described in Section 5.4. Lecithin is the commercial name given to a mixture of phospholipids, naturally occurring in animal or vegetable products such as egg yolk (8-10% phospholipids), butter (0.5-1.2%), wheat lipids (approx. 0.5%) soybean (1.5-3%) and other oil seeds. More details on the chemical composition and physical properties of lecithin appear in Sections 2.3,3.11,6.3,8.10 and 11.2. 

Table 17.1 presents the chemical composition of different vegetable fibers. Compared to the other fibers, wheat straw shows rather low cellulose content, a high lignin composition, but also a high ash content linked to a high silica fraction. Silica is mainly located on the leaves, 12% of ash in the leaves compared to, for example, 6% in the intemodes. Average value is 7-8% of ash in the straw. 

Lehman ME, Blum U (1999) Evaluation of fendic add uptake as a measurement of allelochemical dose effective concentration. 1 Chem Ecol 25 2585-2600 Li X, KeUaway RC, Ison RL, Annison G (1992) Chemical composition and nutritive value of mature annual legumes for sheep. Animal Feed Sci Tech 37 221-231 Liebl RA, Worsham AD (1983) Inhibition of morning-glory Ipomoea lacunosa L.) and certain other weed species by phytotoxic components of wheat (Triticum aestivum L.) straw. J Chem Ecol 9 1027-1043... 

Stubbs TL, Kennedy AC, Reisenauer PE, Burns JW (2009) Chemical composition of residue from cereal crops and cultivars in dryland ecosystems. Agron J 101 538-545 Sylvia DM, Fuhrmann JJ, Hartel PG, Zuberer DA (2004) Principles and application of soil microbiology, 2nd edn. Prentice Hall, New Jersey, NJ Tang CS, Waiss AC (1978) Short-chain fatty acids as growth inhibitors in decomposing wheat straw. J Chem Ecol 4 225-232... 

Natural fibers vary widely in chemical composition, stmcture, and dimension and are obtained from different parts of the plants. Natural fibers, such as jute, ramie, flax, kenaf, and hemp are obtained from the stem abaca, sisal, banana and pineapple from the leaf cotton, coir, and kapok from the seed grass, and reed fibers (com, rice, and wheat) [4]. Climatic conditions, age, and fiber extraction... 

Table 15.8. Chemical composition of anatomical parts of a wheat kernel (average weight-% on dry weight basis)...

Bread flours are standardized on the basis of their ash content in Europe and, particularly, Germany. The type of flour = ash content (weight %) x 1000 corresponds to the extraction grade. Examples are provided in Table 15.36 for wheat and rye flours and their chemical composition... 

Desulphated keratan sulphate has been shown to interact with wheat-germ agglutinin, supporting the view that non-consecutive (1 -> 4)-2-acetamido-2-deoxy-j8-D-glucopyranosyl residues interact specifically with the lectin to precipitate the complex. The distribution and chemical composition of keratan sulphate in various tissues, including those from a patient with Marfan syndrome, have been related to ageing. 

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