Wheat lipid composition

TABLE 5. Nonpolar Acyl Lipid Composition of Laboratory Extracted Wheat Germ Oil. ... 

Diuron is a particularly potent inhibitor of the Hill reaction (Table I), but it does not significantly alter membrane lipid composition. The possibility that the effects of the pyridazinones on membrane lipids result from pbotooxidation as a secondary consequence of the carotenoid inhibition is not likely. Wheat shoots treated with BASF 13 338 have normal levels of carotenoids and chlorophylls (Table II), but linolenic acid levels are severely depressed (Table III). Thus, inhibition at the lipid site can occur without inhibition at the pigment site. Also, BASF 13 338 preferentially reduces linolenic acid, whereas the double bonds of all the unsaturated fatty acids would be susceptible to photooxidation. San 9774 preferentially alters the fatty acid composition of MGDG compared to DGDG (Table III). The preferential alteration of a single class of membrane lipids is inconsistent with the photooxidation hypothesis. 

Fiber complexes of ten tobacco cultlvars as byproducts of the leaf protein extraction process contain levels of neutral and acid detergent fiber comparable to that of alfalfa fiber and in excess of that in wheat bran. Compositional analyses revealed lesser concentrations of cellulose, lignin, and lipid but a greater amount of hemlcellulose in tobacco than in alfalfa. In reference to wheat bran, tobacco fiber has comparable amounts of Na, P, S,... 

Table 3.210 Lipid composition of fractions from wheat and maize seeds...

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 2. Lipid composition (major acyl lipids) of thyla-koids isolated from leaves of wheat, grown with or without SAN-9789 during seed imbibition. The values are the means SD, n denotes number of independent experiments. MGDG, monogalactosyldiacylglycerol DGDG, digalactosyldiacylgly-cerol SQDG, sulfoquinovosyldiacylglycerol PG, phosphati-dylglycerol.

Starch contains various impurities including proteins, phospholipids and glucose-6 phosphate, but these seldom exceed in total about 3%. The nature and level of impurities is, however, believed to influence the behaviour and properties of the various starches. Wheat, maize and potato starches all have different lipid compositions. Wheat starch has a greater phospholipid content than the maize variety and potato starch has the highest degree of phosphorylation. 

Barnes, P.J. Lipid composition of wheat germ and wheat germ oil. Fette Seifen Anstrichm. 84, 256 (1982)... 

The lipids are preferentially stored in the germ which, in the case of com and wheat, serves as a source for oil production (cf. 14.3.2.2.4). Lipids are stored to a smaller extent in the aleurone layer. Cereal lipids do not differ significantly in their fatty acid composition (Table 15.31). Linoleic acid always predominates. Close attention has been given to wheat lipids since they greatly influence baking quality ttnd they have therefore been studied thoroughly. 

The effect of wheat bran upon bile salt metabolism and upon the lipid composition of bile in gallstone patients. Am.J. Dig.Pis., 21 521 (1976). 

Williams M, She wry PR, Harwood JL. Influence of the "greenhouse effect" on the lipid composition of wheat Triticum aestivum L.) seeds. Gra.sas y Aceites 1993 44 132-34. 

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... 

Gontard, N., Duehez, C., Cuq, J.L., and Guilbert, S. (1994). Edible composite films of wheat gluten and lipids Water vapor permeability and other physieal properties. Int. J. Food Sci. Technol. 29,39 50. 

Two books by C. H. Bailey have become standard references. The first (59) covers wheat as a raw product and is concerned with varieties and environment in respect to composition, the milling process and its effects on the milled products, and the characteristics of flour. The second (60) is primarily a biochemical study concerned with the proteins, starches, sugars, gums, lipids, minerals, and vitamins of the wheat kernel. Both are extensively documented. 

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