Native gluten

The cohesive-elastic character of gluten is the basis for many vegetarian-simulated meat products where it holds ingredients and provides chewy texture. It must be cautioned that, because of its highly cohesive properties, native gluten may not be compatible with and serve as an adhesive for some ingredients. 

High molecular weight and random coil structure of protein result in more associations and thereby enhance adhesive and cohesive properties. Although these characteristics are inherent in native gluten proteins, functional properties of other proteins may be improved by chemical or thermal processing. 

Figure 2. Amount of free amino groups (A) and solubility at pH 3 and 11 (B) of wheat gluten as a function of pH (reaction carried out at RT, 4 hrs, COOH NHS EDC=l S 5). The amount of amino groups in native gluten was 14,8 mmol/100 g protein ( ). The solubility of native gluten was 58% at pH 3 ( ) and 67% at pH 11 (O).

Figure I. Effect of glycerol concentration in the film-forming solution on mechanical properties. 1A deamidated gluten at 10%. IB native gluten at 10 %...

Production Fresh native gluten, as well as dried or devitalized gluten, with at least 70% protein are the raw materials. Hydrolysis is performed, in rubber- or plastic-lined, stirred autoclaves with steam jacket, on 1 1 1-mixtures of dry gluten, water and concentrated hydrochloric acid at a 113-116 °C for 8-12 hours. 

EsterificaticMi with a fatty alcohol modified the functional properties of proteins, particularly their solubility in alkaline water. For wheat gluten and sunflower esterified proteins, solubility at basic pH decreased compared to native proteins, indicating thus a hydrophobation effect Fig 4 shows the effect of esterification on solubility of sunflower proteins. The solubility of unmodified sunflower proteins increased significantly in alkaline media and... 

The experiments were done with industrial glutens, native and deamidated at 20 % provided by Amylum. Putrescine, cadaverine, hexyldiamine, 1-8 diaminooctane, and glycerol were purchased from Sigma Chemical Co. Transglutaminase (1 U/mg) was supplied by Ajinomoto. Transglutaminase (Tgase) activity was determined according to the colorimetric hydroxamate procedure of Folk. ... 

Micard V, Guilbert S. Thermal behaviour of native and hydrophobized wheat gluten, gliadin and glutenin-iich fractions by modulated DSC, Int. J. Biol. Macromol. 27 (2000) 229. 

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