Gluten, composition

Olabarrieta, I., Gallstedt, M., Ispizua, I., Sarasua, J.-R. and Hedenqvist, M.S. (2006). Properties of aged montmorillonite-wheat gluten composite films. Journal of Agricultural and Food Chemistry, 54(4), 1283-1288. 

Hemsri, S., Grieco, K., Asandei, A., and Parnas, R. [2012]. Wheat gluten composites reinforced with coconut fiber. Composites Part A, 43[7], 1160-1168. 

Seven diets were constructed from purified natural ingredients obtained from either C3 (beet sugar, rice starch, cottonseed oil, wood cellulose, Australian Cohuna brand casein, soy protein or wheat gluten for protein) or C4 foodwebs (cane sugar, corn starch, com oil, processed corn bran for fiber, Kenya casein for protein) supplemented with appropriate amounts of vitamins and minerals (Ambrose and Norr 1993 Table 3a). The amino acid compositions of wheat gluten and soy protein differ significantly from that of casein (Ambrose and Norr 1993). 

Plant extracts containing xanthophyll diesters are saponified in composition of propylene glycol and aqueous alkali to form crystals crystallization of xanthophylls is achieved without use of organic solvents crystals are isolated and purified Xanthophylls obtained from corn gluten meal at 50 C using ethanol with ethoxyquin as antioxidant... 

Friedman (21) studied the effect of pH on the amino acid composition of wheat gluten. At pH 10.6 and above (65 C, 3 hours) no cystine was present. LAL increased with pH above 10.6. Lysine decreased over the same range of pH s, while serine and threonine contents dropped sharply at pH 13.9. Friedman concluded that cystine is most sensitive to alkali and that LAL will form most readily if lysine residues are in proximity to the dehydroalanine formed from cystine. Thus, he explained that different steric considerations may explain the different susceptibilities of wheat gluten, casein, and lactalbumin to LAL formation. 

Ingredients. All ingredients were obtained commercially along with compositional information and consisted of corn starch (National Starch, Bridgewater, NJ), whey protein concentrate (WPC) and sodium caseinate (SC) (Leprino Foods, Denver, CO), defatted soy flour (DSF) (Archer Daniels Midland, Decatur, IL), soy protein concentrate (SPC) (Central Soya Company, Fort Wayne, IN), and gluten (G) (Ogilvie Mills Ltd., Montreal, Canada). 

Zhang, X., Do, M.D., Hoobin, P. and Burgar, I. 2006. The Phase Composition and Molecular Motions of Plasticized Wheat Gluten-Based Biodegradable Polymer Materials Studied by Solid-State NMR Spectroscopy. Polymer, 47, 5888-5896. 

Thermo-mechanical analysis (TMA)26 and DMTA292 have been used to study the viscoelastic properties of bread, a composite two-phase system. The moisture dependence of Tg was similar to that of pure amorphous starch and gluten.242,282 293-295 At the moisture content of bread, water exerts its full plasticization effect on the composite polymer matrix, reducing the effective Tg to about -10° to - 12°C,26,292 well below normal shelf life storage temperatures of this product. 

The amino acid composition of alkali-treated casein, lactal-bumin, and wheat gluten are given in Tables I-III. The results show that the following amino acids are destroyed to various extents under basic conditions threonine, serine, cystine, lysine, and arginine, and possibly also tyrosine and histidine. The losses of these amino acids is accompanied by the appearance of lysinoalanine and other ninhydrin-positive compounds. 

For example, the respective values at pH 10.6 are 0.262, 0.494, and 1.04 mole per cent (ratio of about 1 2 4) at pH 11.2 the values are 0.420, 0.780, and 1.32 mole per cent and at pH 12.5 (pH of 1% protein solution in 0.IN NaOH), the respective values are 0.762, 0.780, and 2.62 mole per cent. (Note that the value of casein approaches that of gluten at this pH). The observed differences in lysinoalanine content of the three proteins at different pH values are not surprising since the amino acid composition, sequence, protein conformation, molecular weights of protein chains, initial formation of intra- versus intermolecular crosslinks may all influence the chemical reactivity of a particular protein with alkali. Therefore, it is not surprising to find differences in lysinoalanine content in different proteins treated under similar conditions. These observations could have practical benefits since, for example, the lower lysinoalanine content of casein compared to lactalbumin treated under the same conditions suggests that casein is preferable to lactalbumin in foods requiring alkali-treatment. 

Effect of pH on amino acid composition of wheat gluten. Conditions 1% wheat gluten 65°C 3 hours. 

Celiac patients must avoid gluten in order to restore their absorptive surface towards normal. For most patients this involves a lifetime of careful scrutiny of the composition of manufactured foods and elimination of many popular commercial products from their diet. 

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. 

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