**1. Introduction**

Cereals crops on a global scale are the largest (or most spread) sources of proteins. Among them, wheat occupies an important place, the world production of which has increased from 450 million tons in 1981–750 million tons at present. Wheat is the only type of grain crop

© 2016 The Author(s). Licensee InTech. This chapter is distributed under the terms of the Creative Commons Attribution License (http://creativecommons.org/licenses/by/3.0), which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited. © 2018 The Author(s). Licensee IntechOpen. This chapter is distributed under the terms of the Creative Commons Attribution License (http://creativecommons.org/licenses/by/3.0), which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited.

from which spare proteins in the dry wheat gluten (DWG) form were extracted industrially, intended as a protein ingredient to improve the baking properties of flour and meat substitution in sausage products. In time of processing of wheat grains on DWG forms bran, which is additionally a source of valuable food protein. Therefore, this chapter is devoted to the results of a study of the physicochemical properties of DWG proteins and protein concentrates from wheat bran for the purpose of applying the information obtained for practical purposes to improve and regulate the functional properties of protein ingredients in the development of food formulas.

biochemical composition, and physicochemical properties of the polypeptides themselves are practically not are considered. Despite the fact that, for example, dry wheat gluten (DWG) is widely used in the production of bread as an improver or filler [15–19], the areas of its use can

Interrelation of Functional Properties of Protein Products from Wheat with the Composition…

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The choice of DWG is conditioned not only by the fact that wheat is one of the traditional cultures of many peoples of the world for bread production but also because the increasing volumes of its cultivation are aimed at producers to use it in technologies and other types of food products. In addition, the amount of secondary products of wheat processing in the form of bran is also increasing. Taking into account the functional properties on the basis of DWG, we have developed special mixtures for the production of oil cakes and protein-containing biscuits [20], based on the gel-forming and foaming ability—marshmallows with the replacement of egg protein on DWG [21], based on enzymatically hydrolyzed DWG-bread with increased content protein from amaranth (20–25%) for diabetics (unpublished data). However, the processes of modifying the functional properties of protein products from wheat, the prophylactic and dietary properties of products from them, can be more effective if one has more information about the structural features and properties of their proteins, as it is known for proteins from other cultures [22–24] that additional studies are needed on the characteristics of the composition and properties of protein products from wheat, are the following facts. Thus, it is known that soluble proteins have a greater set of functional properties than poorly soluble proteins. They have little change in viscosity, gelatinization, but they have a high ability to stabilize suspensions, emulsions, and foams. However, there are proteins that do not fall under these patterns. So DWG proteins, despite their low solubility in water (1–3%), form structured gels that withstand heating, freezing, and drying. Therefore, they are used to prepare protein fibers as a binding agent in the production of film membranes, meat

Another example is protein flour made from wheat bran. Having relatively low solubility values (10–20%), it has a high fat-emulsifying ability (FEA) and foaming capacity (FC): 72–97% and 74–100%, respectively [2, 3]. It is possible to increase the solubility of proteins to 25–100% by heating to 40–90°C, changing the ionic strength of the system or pH [3], but it is difficult to predict the final result of solubility control, as well as other functional properties, because it will often have a "one-time" nature and do not provide, as a rule, a stable forecasting of the quality of finished products. Hence, in order to predict stable results of the modification of the quality of protein products, the purpose of the present study was to study the composition and physicochemical properties of DWG proteins and products from wheat bran and to establish a correlation relationship between the results and the basic functional properties of the ingredients.

As protein products, two samples of dry wheat gluten were used from LLC "BM" (Kazakhstan) and "Royal Ingredients Group BV" (the Netherlands), as well as concentrates from wheat

be expanded by modifying the functional properties.

analogs, and non-food products [25, 26].

**2. Materials and methods**

**2.1. Materials**

Functional properties of protein products are understood as physicochemical indicators that determine the behavior of proteins in the production of food products, providing the necessary structure, and consumer properties [1]. The indicators characterize the parameters of products, some of which are substituted or supplemented with protein in the technological processes of food production. The functional properties of protein products are evaluated both in numerical values and in profiles of dependencies on various technological factors (temperature, pH, processing time, etc.) [2–5]. This approach to the evaluation of properties is reflected in the term "techno-functional," which includes the features of the reactivity of proteins in the technological processes of production and storage of food systems. Functional properties for concrete food systems are usually evaluated on model recipes, and then compared with the properties of traditional or known protein products. The presence of hydrophilic and hydrophobic groups in one chain ensures the interaction of proteins with water, lipids, carbohydrates, other compounds and leads to the formation of stable emulsions, foams, gels, and so on. In solutions proteins can perform a dispersing and suspending roles, it's able to cling to solid particles and by that forming cementing structures. The presence of polar and nonpolar, charged and uncharged groups in one polymer chain allows proteins to interact with different types of compounds and, thereby, influence the quality of food products.

The most important functional properties of protein products are hydration, fat-binding capacity, foam ability, stability of emulsions, foam stability (FS), gel-forming ability, adhesion, rheological properties (viscosity, elasticity), ability to spin and texturing [1, 6, 7]. The values of the functional properties of protein products always determine the directions of their use in the production of food products as technological or nutritional ingredients, but not always these properties satisfy the requirements of the consumer; therefore, in the chemistry of dietary protein, there is a direction devoted to regulating the quality indices of vegetable protein products by various modification processes [8–12].

It is known that the functional properties of protein products depend on the chemical nature of the raw materials (wheat, rye, soybean, etc.), methods of isolation, processing, and technological regimes of food production (pH, temperature, recipe, etc.) [13–14]. When analyzing the nature of vegetable proteins, food recipes' designers limit themselves, as a rule, to a statement of facts showing how a particular kind of raw material affects the functional properties but does not study the molecular basis that conditions these properties. In the practice of using protein products, at best, technological factors affecting their functional properties (temperature, pH, electrolytes, etc.) are taken into account, whereas the characteristics of the chemical, biochemical composition, and physicochemical properties of the polypeptides themselves are practically not are considered. Despite the fact that, for example, dry wheat gluten (DWG) is widely used in the production of bread as an improver or filler [15–19], the areas of its use can be expanded by modifying the functional properties.

The choice of DWG is conditioned not only by the fact that wheat is one of the traditional cultures of many peoples of the world for bread production but also because the increasing volumes of its cultivation are aimed at producers to use it in technologies and other types of food products. In addition, the amount of secondary products of wheat processing in the form of bran is also increasing. Taking into account the functional properties on the basis of DWG, we have developed special mixtures for the production of oil cakes and protein-containing biscuits [20], based on the gel-forming and foaming ability—marshmallows with the replacement of egg protein on DWG [21], based on enzymatically hydrolyzed DWG-bread with increased content protein from amaranth (20–25%) for diabetics (unpublished data). However, the processes of modifying the functional properties of protein products from wheat, the prophylactic and dietary properties of products from them, can be more effective if one has more information about the structural features and properties of their proteins, as it is known for proteins from other cultures [22–24] that additional studies are needed on the characteristics of the composition and properties of protein products from wheat, are the following facts. Thus, it is known that soluble proteins have a greater set of functional properties than poorly soluble proteins. They have little change in viscosity, gelatinization, but they have a high ability to stabilize suspensions, emulsions, and foams. However, there are proteins that do not fall under these patterns. So DWG proteins, despite their low solubility in water (1–3%), form structured gels that withstand heating, freezing, and drying. Therefore, they are used to prepare protein fibers as a binding agent in the production of film membranes, meat analogs, and non-food products [25, 26].

Another example is protein flour made from wheat bran. Having relatively low solubility values (10–20%), it has a high fat-emulsifying ability (FEA) and foaming capacity (FC): 72–97% and 74–100%, respectively [2, 3]. It is possible to increase the solubility of proteins to 25–100% by heating to 40–90°C, changing the ionic strength of the system or pH [3], but it is difficult to predict the final result of solubility control, as well as other functional properties, because it will often have a "one-time" nature and do not provide, as a rule, a stable forecasting of the quality of finished products. Hence, in order to predict stable results of the modification of the quality of protein products, the purpose of the present study was to study the composition and physicochemical properties of DWG proteins and products from wheat bran and to establish a correlation relationship between the results and the basic functional properties of the ingredients.
