Food protein functional properties

The functionality of a protein is dictated by the molecular properties of the protein as modified by processing treatments, environmental factors, and interactions with other components. Environmental conditions, such as pH, ionic strength, type of salts, moisture content, and oxidation-reduction potential, may alter the functional properties of a protein in a food. Protein functional properties are also influenced by unit operations during processing... 

As presented, data are available on assessment of water absorption in simple systems and on the incorporation of protein additives into some food systems. Functional properties in... 

The expanded use of enzymes to modify protein functional properties has great promise for the food industry. Major advantages of using proteases compared to other agents include their specificity, their effectiveness at low concentrations and... 

One of the most important factors that determine whether or not a protein is usable in the fabrication of a food product is its functionality. The functionality results from a combination of physico-chemical properties that define the behavior of the food protein in food systems. It is evident that a detailed understanding of food protein functionality requires an intimate knowledge of the protein structure. The bovine milk protein system has been studied in great detail. Although providing useful structure-function... 

Rahma, E.H. and Abd El Aal, M.H. (1988) Chemical characterisation of peach nut oil an protein functional properties, in vitro digestibility and amino acids profile of flour. Food Chem., 28,31—43. Raie, M.Y. and Salma, S. (1985) Sesamum indicum and Papaver somniferum oils. Fette Seif Anstrichm., 87, 246-247. 

This selective review, which deals primarily with the chemical modification of soy proteins, is further limited to nondestructive chemical reactions which alter physical and biochemical properties of importance in food systems. Soy protein products have been modified by various chemical reactions including (a) treatment with alkalies and adds, (b) acylation, (c) alkylation and esterification, and (d) oxidation and reduction. In most instances these reactions have been applied to heterogeneous protein mixtures containing nonprotein impurities, and often to proteins of unknown prior history. Nonetheless, these reactions indicate that protein functional properties of value in food fabrication can be altered significantly through reaction with chemical reagents. It is recognized that chemically modified proteins must be critically evaluated for food safety. 

Functional properties of canola protein products can be improved by succinylation (130,131). Controlled acetylation can reduce undesirable phenoHc constituents as well (132). However, antinutrients in canola and other vegetable protein products such as glucosinolates, phytic acid, and phenoHc compounds have severely limited food appHcations of these products. 

Hydrolyzed Vegetable Protein. To modify functional properties, vegetable proteins such as those derived from soybean and other oil seeds can be hydrolyzed by acids or enzymes to yield hydrolyzed vegetable proteins (HVP). Hydrolysis of peptide bonds by acids or proteolytic enzymes yields lower molecular weight products useful as food flavorings. However, the protein functionaHties of these hydrolysates may be reduced over those of untreated protein. 

Oilseed proteins are used as food ingredients at concentrations of 1—2% to nearly 100%. At low concentrations, the proteins are added primarily for their functional properties, eg, emulsification, fat absorption, water absorption, texture, dough formation, adhesion, cohesion, elasticity, film formation, and aeration (86) (see Food processing). Because of high protein contents, textured flours and concentrates are used as the principal ingredients of some meat substitutes. 

WANG M, HETTiARACHCHY N s, Qi M, BURKS w, siEBENMORGEN T (1999) Preparation and functional properties of rice bran protein isolate. J Agri, Food Chem, 47 411-16. 

Chemical and Functional Properties of Food Proteins Edited by Zdzislaw E. Sikorski... 

The consumption of dairy products plays a significant role in providing high-quality protein, vitamins, minerals, and other bioactive compounds to the American diet. Dairy products are consumed fresh in the United States in the form of fluid milk, cheese, yogurt, butter, and ice cream. Dried and condensed products such as nonfat dried milk, whey, whey protein concentrates, and isolates are also produced which are used as ingredients to boost the nutritional and functional properties of a host of other food... 

Matthey, F. P. and Hanna, M. A. (1997). Physical and functional properties of twin-screw extruded whey protein concentrate-corn starch blends. LWT Food Sci. Technol. 30,359-366. 

Morr, C. V. and Ha, E. Y. (1993). Whey protein concentrates and isolates Processing and functional properties. Grit. Rev. Food Sci. Nutr. 33, 431-476. 

Queguiner, C., Dumay, E., Cavalier, C., and Cheftel, J. C. (1989). Reduction of Streptococcus thermophilus in a whey protein isolate by low moisture extrusion cooking without loss of functional properties. Int. ]. Food Sci. Technol. 24, 601-612. 

Tolstoguzov VB (1986) Functional properties of protein-polysaccharide mixtures. In Mitchell JR, Ledwards, DA (eds) Functional properties of food macromolecules. Elsevier, London, p 385... 

Compositional differences in the pea seeds influence the quality of the end products. Pea flours have been used for protein enrichment of a number of cereal-based products however, undesirable sensory characteristics may limit their use, in spite of improved functional effects in food systems. The production of volatile compounds during cooking and baking of foods with pea supplementation affects their acceptability. Enzyme systems active in unheated pea flours may contribute to their functional properties, but adversely affect the sensory quality of the food. 

Characteristically, legume seeds are rich in protein and contain intermediate to high levels of lysine and threonine which are important in balancing the deficiencies of these essential amino acids in cereal diets. Certain legume proteins, such as soybean, also exhibit strong functional properties, especially water solubility, water and fat binding and emulsification. Thus soybean flours, protein concentrates and isolates have been used widely as nutritional supplements and functional ingredients in foods. 

Sikorski, Z.E. (2002). Chemical reactions of proteins in food systems, in Sikorski, Z.E., ed.. Chemical and Functional Properties of Food Proteins, CRC Press, Boca Raton, 191-216. 

A peptide is essentially comprised of L-amino acid residues, and the peptide backbone may be critical to provide physicochemical and functional properties. Diverse functionalities induced by peptides in natural protein hydrolysates are being received with much interest in food industries or alternative-medicinal food sciences. The latest year s researches... 

Proteins are important food components mainly due to their nutritional and functional value. Dietary proteins provide amino acids and nitrogen necessary for organisms. They also play a major role in determining the sensory and textural characteristics of food products. The functional properties are related to their ability to form viscoelastic networks, bind water, entrap flavors, emulsify fat and oil, and form stable foams [105]. 

The increasing interest in nutritional and functional properties of soybean protein has promoted their use in the manufacturing of foods for human consumption. Soybean products (particularly infant formulas and soybean dairy-like) may also represent an interesting substitute for infants and people allergic to milk proteins. On the other hand, due to their technological properties and low cost, soybean proteins are increasingly employed as ingredients in milk, bakery, and meat products, in which their addition is forbidden or allowed up to a certain limit. 

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],... 

FIGURE 5.6 Physico-chemical and protein-related functional properties of defatted morama bean flours and their potential applications in food systems (adapted from Maruatona, 2008). 

These transglutaminase-catalysed reactions can be nsed to modify the functional properties of food proteins. Transglutaminase has been nsed to catalyze the cross-hnking of a nnmber of proteins, such as whey proteins, soy proteins, glnten, myosin and... 

Lokra, S., Helland, M. H., Claussen, I. C., Straetkvern, K. O., Egelandsdal, B.10.1016/j.lwt.2007.07.006 (2007). Chemical characterization and functional properties of a potato protein concentrate prepared by large-scale expanded bed adsorption chromatography. LWT - Food Sci. Technol. 

---