Effect of protein content

The protein content of biological fluids is not only a potential source of variation during the collection of samples, but also causes considerable 

Zinc and copper, however, are present in low concentration and sufficient dilution to overcome viscosity and aspiration difficulties may so reduce the concentration that sensitivity is unsatisfactory. This is an important consideration and a number of techniques for resolving the problem have been suggested. 

The average adult contains more that 1 kg of calcium, this being the most prevalent metallic element. The major proportion is contained within the bone (99%) the remainder being in teeth and soft tissues [20]. Plasma calcium represents only a minute fraction (0.03%) of total body calcium yet alteration in the concentration of this fraction can usually accurately reflect underlying disorders of calcium metabolism which are of great importance in clinical medicine. 

Not all calcium present in the diet is absorbed by the small intestine and mechanisms are present to ensure only amounts appropriate to body needs are absorbed. These processes are complex and involve the interaction of special transport protein, vitamin D and parathormone. Thus, abnormalities of calcium metabolism may result from many different disease processes. Diseases affecting the bowel may prevent normal absorption, diseases of the parathyroid gland may result in inappropriate levels of parathormone for calcium requirement and a nutritionally inadequate diet may cause vitamin D deficiency with consequent disordered calcium absorption. 

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Crosbie et al. (11-13) carried out a detailed validation that showed that the NIR calibration could predict water absorption beyond the effects of protein content and hardness, both known to exert a strong effect on the spectra. This was achieved by applying the calibration to a subset of samples for which water absorption had a low correlation with PSI and flour protein. 

Kim, ).T. and Netravali, A.N. (2010) Effect of protein content in soy protein resins on their interfacial shear strength with ramie fibers. /. Adhes. 

The calcium content of the meals was increased by adding milk or lowfat cheese. In the studies on the effect of protein, the animal protein sources were milk, cheese, boiled beef and boiled egg. To further increase, the protein content without at the same time increasing the calcium or zinc content, sodium caseinate was used in one meal. 

Although zooplankton tend to maintain a rather rigid biochemistry, intra- and interspecific differences may arise due to physical characteristics (e.g., water content, body size), developmental stage, as weU as location (e.g., latitude) and season. Increased water content, and thus decreased muscle tissue, leads to a decrease in protein and N content in zooplankton (ChUdress and Nygaard, 1974 Morris and Hopkins, 1983). This may explain the lower N and protein content in gelatinous zooplankton relative to crustaceans as described above. The effect of water content on proteins can also be seen within taxonomic groups. For example, Calanus paciftcus... 

Hence, in products from D to I, which were the supernatants obtained after dilution, decantation, and centrifugation of previous products, respectively, significant drops in protein and lipid levels were observed in comparison with the initial product composition (Table 21.12). Only samples H and I had a protein level different from the other samples (Table 21.12). The decrease of protein content was of 9% and 8%, respectively, for these products. This suggests that a part of the protein in the supernatants has precipitated. This could be explained by their lower ionic strength (conductivity of 0.4—0.8 mS/cm). Products D, E, F, and G had similar protein contents. In a general manner, the acidification by EDBM followed by a dilution resulted in the preservation of more than 90% of the protein present initially. For the fat content, the more important decrease was observed for products E and F with a respective reduction of their lipid contents of 73% and 66%. In second position are products H and I with 49% and 45% respective reduction of lipids levels (Table 21.12). These different precipitation levels might be explained by the initial fat contents of the products. Effectively, products E and F obtained from samples B and C contained between 0.72% and 0.78% of fat while products H and 1 obtained from products Bi and Ci have fat levels between 0.47% and 0.55%. Samples dilution following the EDBM step resulted in a reduction of lipids from 0.78% to 0.21%, a decrease of nearly 73% of initial content in WPC lipids. It also resulted in clarified supernatants with a low level in hpids and with the majority of the proteins present initially. 

Aguilera, J.M., Levi, G., and Karel, M. Effect of water content on the glass transition and caking of fish protein hydrolysates. Biotechnology, 9, 651, 1993. 

Netto, EM., Desobry, S.A., and Labuza, T.P. Effect of water content on the glass transition, caking and stickiness of protein hydrolysates, Int. J. Food Prop., 1, 141,1998. 

After proving that whole egg powder with corn syrup and salt was more hygroscopic than whole egg powder alone (higher fat content and protein hydrophobicity), Lai et al. (1986) studied the effect of moisture content on compressibility (C2). Moisture content (3-14% dry basis) had almost no effect on the compressibility of whole egg powder, because a higher concentration of lipids was the dominant factor influencing flow properties. However, whole egg powder mixed with corn syrup and salt had a maximum compressibility of about 4.0% dry basis moisture. At this maximum, an increase in bulk density and a decrease in tensile strength were observed. 

Effect of Amide Content on Thermal Generation of Maillard Flavor in EnzymaticaUy Hydrolyzed Wheat Protein... 

Stodolnik, L. and Knasiak, M., 1981, Effect of fat content and freezing rate on solubility of myofibrillar proteins and texture properties of minced fish flesh, Refrigeration Sci. TechnoL, 4, 429. 

Controls were incorporated so that any effects of protein handling (e.g., the concentration step) could be allowed for. The eluted protein showed a loss of ouhelix content of the order of 50% relative to the "native" unexposed fibrinogen, so that surface interactions appear to be capable of disrupting o-helical regions of the protein. It should be noted that we could not distinguish in these experiments between indiscriminate desorption of whole protein with an overall reduction of o-helix content and preferential desorption of portions of the molecule with inherently low o-helix content. 

Perez-Gago, M.B., Serra, M., Alonso, M., Mateos, M., del Rfo, M.A. Effect of solid content and lipid content of whey protein isolate-beeswax edible coatings on color change of fresh-cut apples. J. Food Sci. 68(7), 2186-2191 (2003)... 

This review focuses on the extraction of lipids from plant and muscle tissues using supercritical CO2 with an emphasis on the effect of structural and compositional differences as well as C02/lipid/protein/water interactions. The effect of moisture content ranging from 3-20% in oilseeds to 3-64% in muscle tissues on hpid and water extractability and residual proteins is demonstrated. 

The effect of plasticizer content on the thermal degradation of soy protein films has been investigated by Guerrero and de la Caba (2010) and Guerrero et al. (2010). 

Figure 11.5 Effect of water content on the Tg and minimum thermosetting temperature (TJ for wheat gluten proteins [163]. Hoseney and co-workers [163] (0), Kalichevski and co-workers [164] ( ), Nicholls and co-workers (O), Cherian and Chinachoti [154] (A), and Pouplin and co-workers [187] (X) the thermosetting temperature ( ) was determined for wheat glutenins [166]...

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