Proteins nutritive value

The Protein Equivalence Ratio (PER), a criterion for protein nutritional value, is higher for the gel produced protein. 

Table IV. Protein Nutritive Value of Raw and Cooked Red Gram (20)...

Furosine, a marker of the Maillard reaction product, is a valuable indicator of food protein quality. It is a marker for thermal treatment in foodstuffs and is directly related to the loss of lysine availability. IPC was employed to determine furosine content in beverages based on soy milk and cow milk supplemented with soy isoflavones [39]. Furosine was also analyzed in 60 commercial breakfast cereals to assess their protein nutritional values. The higher the protein content in the formulation, the higher the furosine levels [40]. A simple IPC technique that uses 1-octanesulfonic acid as the IPR allowed the selective determination of histamine levels in fermented food [41]. 

Blends of peanut/chickpea, wheat/chickpea, rice/chickpea, peanuVsoybean, sunflower/maize, and cowpea/rice have all shown improved nutritional qualities with supplementation of sesame meal. Even more significant, however, is the finding that a simple blend of one part sesame and one part soy protein has about the same protein nutritive value as casein, the main protein of milk. The high-lysine and low-methionine content of soy protein is complementary to sesame protein. 

Following the formation of the deoxyketosyl derivative, the reactions leading to the formation of the brown pigments or melanoidins (Fig. 3) are not well defined. These reactions, however, are responsible for numerous flavours and odours, possibly for toxicity, and for a further reduction in protein nutritive value via destruction of amino acids and reduced digestibility. There are thought to be three main pathways in the advanced Maillard reaction. 

Table 11. Nutritive Value of Leaf Protein Concentrates and Other Protein Products ...

In general, nonconventional protein foods must be competitive with conventional plant and animal protein sources on the bases of cost delivered to the consumer, nutritional value to humans or animals, functional value in foods, sensory quality, and social and cultural acceptability. Also, requirements of regulatory agencies in different countries for freedom from toxins or toxic residues in single-cell protein products, toxic glycosides in leaf protein products, pathogenic microorganisms, heavy metals and toxins in fish protein concentrates, or inhibitory or toxic peptide components in synthetic peptides must be met before new nonconventional food or feed protein products can be marketed. 

Protein Content. The protein content of milk can be determined using a variety of methods including gasometric, Kjeldahl, titration, colorimetric, and optical procedures (see Proteins). Because most of the techniques are too cumbersome for routine use in a dairy plant, payment for milk has seldom been made on the basis of its protein content. Dye-binding tests have been appHed to milk for determination of its protein content these are relatively simple to perform and can be carried out in dairy plant laboratories. More emphasis will be given to assessing the nutritional value of milk, and the dependence on fat content as a basis for payment will most likely change. 

Pea.nuts, The proteins of peanuts are low in lysine, threonine, cystine plus methionine, and tryptophan when compared to the amino acid requirements for children but meet the requirements for adults (see Table 3). Peanut flour can be used to increase the nutritive value of cereals such as cornmeal but further improvement is noted by the addition of lysine (71). The trypsin inhibitor content of raw peanuts is about one-fifth that of raw soybeans, but this concentration is sufficient to cause hypertrophy (enlargement) of the pancreas in rats. The inhibitors of peanuts are largely inactivated by moist heat treatment (48). As for cottonseed, peanuts are prone to contamination by aflatoxin. FDA regulations limit aflatoxin levels of peanuts and meals to 100 ppb for breeding beef catde, breeding swine, or poultry 200 ppb for finishing swine 300 ppb for finishing beef catde 20 ppb for immature animals and dairy animals and 20 ppb for humans. 

The application of biosolids also increases the nutritional value of blue grama. Tissue levels of nitrogen, phosphorus, potassium, and crude protein increased to recommended tissue concentrations with biosolids treatments. Trace metals in blue grama grass did not increase during the study, thereby eliminating concerns that toxic amounts of these elements could be transferred to grazing animals. 

MARIOTTI F, MAKE S, BENAMOUZIG R, LUENGO 0, DARE S, GAUDICHON 0, TOME D (1999) Nutritional value of [15N]-soy protein isolate assessed from ileal digestibility and postprandial protein utilization in humans. /AmZ 129 1992-7. 

Polyphenols are ubiquitous in all plant organs where they are found as monomers or in polymerised forms (Schofield et al, 2001). In addition to the beneficial effect of poljq)henols, they also bind minerals and precipitate proteins and carbohydrates, in effect reducing the nutritive value of foods. Polyphenols have been classified for nutritional purposes into extractable and non-extractable types (Bravo, 1998). Extractable polyphenols are low-and intermediate-weight phenolics while non-extractable polyphenols have high molecular weight and are insoluble in normal solvents. 

Friedman, M., Gumbmann, M. R., and Ziderman, 1.1. (1987). Nutritional value and safety in mice of proteins and their admixtures with carbohydrates and vitamin c after heating. J. Nutr. 117, 508-518. 

Interest in seed and vegetable proteins has been growing steadily over the past two decades because of the major role plant proteins play in both human and animal diets. Animal proteins are still acknowledged to have higher nutritional value than those from plant sources but for economic, health, or religious reasons,... 

Despite the wealth of information available on the biochemistry, genetics, and nutritional values of plant proteins, people eat foods that look, smell, and taste good not because of nutritional importance. Thus, new blended plant foods or protein-supplemented snacks or food products will have to look and taste like the traditional items if they are to gain sufficient acceptance to become commercially feasible. Absolute food... 

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