Wheat proteins functional properties

Protein-Based Substitutes. Several plant and animal-based proteins have been used in processed meat products to increase yields, reduce reformulation costs, enhance specific functional properties, and decrease fat content. Examples of these protein additives are wheat flour, wheat gluten, soy flour, soy protein concentrate, soy protein isolate, textured soy protein, cottonseed flour, oat flour, com germ meal, nonfat dry milk, caseinates, whey proteins, surimi, blood plasma, and egg proteins. Most of these protein ingredients can be included in cooked sausages with a maximum level allowed up to 3.5% of the formulation, except soy protein isolate and caseinates are restricted to 2% (44). 

In vitro, the enzyme is able to catalyze crosslinking of whey proteins, soy proteins, wheat proteins, beef myosin, casein, and crude actomyosin (which is refined from mechanically deboned meat), improving functional properties such as the texture of food products [49-53], Bonds formed by transglutaminase exhibit a high resistance to proteolytic degradation [54],... 

Other workers (115-124 for example) have also centered their efforts on the role of phytic acid on zinc and iron bioavailabiliy from both soy and wheat products. It has been suggested (120) that the phytate-to-zinc molar ratio could be used to predict zinc bioavailability in high-phytate foods. Several groups (115, 117), including ours (113), 1 least partially supporT this hypothesis. However, recent work from our laboratory (112) involving soy protein of similar phytate-to-zinc molar ratios clearly demonstrates that zinc bioavailability is also altered by food processing. In this study, zinc from neutralized soy concentrates and isolates was shown to be less available to the rat than was the corresponding acid-precipitated products. This is unfortunate as alkaline conditions are commonly utilized for soy and other plant proteins to obtain beneficial functional properties. 

RB Gupta, IL Batey, F MacRitchie. Relationship between protein composition and functional properties of wheat flours. Cereal Chem 69 125-131, 1992. 

Groninger (38) succinylated fish myofibrillar protein and examined some of its chemical and functional properties. The fish myofibrillar proteins were succinylated at different levels and the degree of succinyla-tion was related to a functional property such as emulsification capacity. The protein efficiency ratio for succinylated protein was lower than that of untreated fish protein. Grant (39) succinylated wheat flour proteins and analyzed their solubility, viscosity, and chromatographic behavior. The effects of acetylation and succinylation on the physicochemical and functional properties of several plant proteins was reviewed recently by Kinsella and Shetty (6). 

The 12 investigations compiled here deal mostly with functional investigations in the food area. Three chapters discuss soy proteins, relating the effects of heat, specific solvents, and enzyme activity on structure and functional properties. Single chapters are concerned with the proteins of wheat, milk, and yeast, respectively, as well as specific crosslinking effects and, enzyme-carrier interactions. Other chapters contrast general functional properties of different proteins. 

SWP is a bland, white creamy low viscous sodium-salt of a soluble wheat protein isolate. By its unique combination of functional properties like emulsifying capacity, gelling, binding, and water-retention, the product can be used in several food applications like meat-preparations, soups, sauces, dressings, imitation dairy, etc. It can also be combined with other functional proteins like caseinates, soy isolates, and may result in all types of synergies. 

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... 

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