Wheat gluten materials

Table 3.12. Mechanical properties of wheat gluten materials plasticized with differ- ...

Figure 3 Life cycle assessment of wheat gluten materials (27)...

Dried Gluten. This material is sold as vital wheat gluten, it is produced by a scaled up version of the process for producing wet gluten for flour testing. A flour and water dough is made and then washed to remove the starch, the soluble proteins and the pentosan-based gum fraction. This latter fraction is an example of a non-starch carbohydrate. 

Schneider et al. (S6, S7, S8) have demonstrated that wheat gluten and certain gluten fractions cause inhibition of the isolated small intestine of the rat. In the Trendelenburg preparation, as modified by Biilbring et al. (B21), inhibition of the peristaltic reflex occurred if the material was placed outside the intestine so that it could reach the muscle without traversing the mucous membrane. If it was placed inside the lumen no inhibitory effect was seen. If the gluten or gluten fractions were incubated with rat mucous membrane extract, complete inactivation of the inhibitory effect was obtained. This action of mucous... 

The ability of a degradable plastic to decay depends on the structure of its polymer chain. Biodegradable plastics are often manufactured from natural polymers, such as cornstarch and wheat gluten. Micro-organisms in the soil can break down these natural polymers. Ideally, a biodegradable plastic would break down completely into carbon dioxide, water, and biomass within six months, just like a natural material. 

Pollard, G. 2005. Catalysis in Renewable Feedstocks -A Technology Roadmap. Report prepared on behalf of The Department of Trade and Industry, Report number CR7656. BHR Solutions Project No 180 2421. http //www.bhrgroup.co. uk/extras/renewcatfull.pdf Pommet, M., Redl, A., Guilbert, S. and Morel, M.-H. 2005. Intrinsic Influence of Various Plasticizers on Functional Properties and Reactivity of Wheat Gluten Thermoplastic Materials. J. Cereal Sci., 42, 81-91. 

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. 

In comparison to isolation of starches from other botanical sources, the industrial isolation of wheat starch is quite unique because different processing techniques may be employed.21,45,70 Kempf and Rohrmann54 described 15 different processes for industrial production of wheat starch and wheat gluten using wheat kernels or wheat flour as the raw material (Table 10.3). Only three of the processes in Table 10.3 are actually used. 

It is also important to remember that wheat gluten and dough are complex materials, consisting not only of protein and water, but also starch-, lipid-, water- and salt-soluble proteins and smaller carbohydrates, and so on. The properties of these materials and their interactions with the gluten proteins are poorly understood but can be expected to also influence the viscoelastic properties. The challenge therefore is to understand gluten structure at the molecular level and how this structure interacts... 

The production of plant derived seasonings from acid hydrolyzed plant proteins is described elsewhere. Recently the acid hydrolysis of plant proteins (wheat gluten, soy protein, etc.) has been questioned especially in the US because of the potential formation of toxic side products. These side products, especially dichloropropanols are formed from plant fats contained in the raw material by the action of concentrated hydrochloric acid which is used in autoclaves at elevated temperatures for hydrolysis [4]. The cancerogenic effect of dichloropropanols has been proven in animal experiments. 

Polymers derived from renewable resources (biopolymers) are broadly classified according to the method of production (1) Polymers directly extracted/ removed from natural materials (mainly plants) (e.g. polysaccharides such as starch and cellulose and proteins such as casein and wheat gluten), (2) polymers produced by "classical" chemical synthesis from renewable bio-derived monomers [e.g. poly(lactic acid), poly(glycolic acid) and their biopolyesters polymerized from lactic/glycolic acid monomers, which are produced by fermentation of carbohydrate feedstock] and (3) polymers produced by microorganisms or genetically transformed bacteria [e.g. the polyhydroxyalkanoates, mainly poly(hydroxybutyrates) and copolymers of hydroxybutyrate (HB) and hydroxyvalerate (HV)] [4]. 

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