Caseinate utilization

Casein hydrolyzates are produced from dried casein. With appropriate heat treatment and the addition of alkaHes and enzymes, digestion proceeds. FoUowing pasteurization, evaporation (qv), and spray drying, a dried product of 2—4% is obtained. Many so-called nondairy products such as coffee cream, topping, and icings utilize caseinates (see Dairy SUBSTITUTES). In addition to fulfilling a nutritional role, the caseinates impart creaminess, firmness, smoothness, and consistency of products. Imitation meats and soups use caseinates as an extender and to improve moistness and smoothness. 

Milk and Milk Replacers. White pan bread was long made with about 3—4% nonfat dry milk (NEDM) in the United States, for reasons of enhanced nutrition, increased dough absorption, improved cmst color, fermentation buffering, and better flavor. Eor some years, however, sharply increased milk prices have led to a decline in its use in breadmaking. Many bakers have turned to the use of milk replacers to control the costs of their products, and these ingredients are now commonly utilized. Milk replacers were designed to dupHcate some of the functions and nutrition of milk. These blends may contain soy flour or cereals, with whey, buttermilk soHds, sodium or calcium caseinate, or NEDM. Milk replacers or NEDM used in bread dough amount to about 1—2%, based on flour. 

The utilization of the vegetable gums, especially those with good filmforming properties, to suspend the solids in paints of the casein and emulsion types, still offers a wide field for experimentation and application. 

Assays utilized conventional ELISA processing except that the reagent volumes were greatly reduced, ranging from 25- to 50-pL well additions. Following a 1-hr block in casein, the monoclonal detection antibody was incubated an additional hour at room temperature. The assay sensihvity from the micro-ELISA was approximately 13.4 ng/mL for rabbit IgG — a result similar to that reported by Silzel et al. (1998). The benefit of the "array of arrays" approach is that 96 samples could be processed for multiple (36 to 144) analytes within the same time interval as a standard single-analyte ELISA. 

McClements, 2006 Anal et al., 2008). Different combinations of proteins and polysaccharides (e.g., P-lactoglobulin + pectin, carrageenan or alginate casein + pectin) have been investigated within the context of multilayer emulsion stabilization (Guzey and McClements, 2006). It seems that the main technical challenge associated with the utilization such complex formation for layer-by-layer emulsion stabilization is the avoidance of bridging flocculation (McClements, 2005, 2006). 

Semenova M.G., Belyakova, L.E., Polikarpov, Yu.N., Antipova, A.S., Anokhina, M.S. (2008). Utilization of sodium caseinate nanoparticles as molecular nanocontainers for delivery of bioactive lipids to food systems relationship to the retention and controlled release of phospholipids in the simulated digestion conditions. In Williams, P.A., Phillips, G.O. (Eds). Gums and Stabilisers for the Food Industry 14, Cambridge, UK Royal Society of Chemistry, pp. 326-333. 

Milk protein products. As indicated in Table 1, the food industry is placing major emphasis on the production and utilization of milk protein products in a wide variety of formulated food products (20,21,22). Although nonfat dry milk (NFDM) and whey powder are major milk protein ingredients in formulated foods, casein and whey protein concentrates, which contain their proteins in a more highly concentrated and functional form, are essential for certain food product applications, such as those products that require the proteins as an emulsifier agent. Additional details on the processing methods and conditions used to produce the various milk protein products are available (23). 

The bioavailability of calcium from dairy foods is considered to be excellent (Schaafsma 1983). Evidence from animal studies suggests that the form of calcium in dairy foods may influence the bioavailability of this mineral (Wong and LaCroix 1980). For example, dairy foods that contain colloidal calcium phosphate or calcium caseinate (e.g., as in Cheddar cheese) appear to be somewhat better sources of calcium than foods that contain ionic calcium (e.g., yogurt, buttermilk). However, calcium in milk and other milk products is of greater bioavailability to humans than calcium found in other food sources. According to Renner (1983), calcium utilization from skim milk powder is 85% compared with 22-74% from vegetables. Dietary fiber in plant cell... 

Fractionation of milk and titration of the fractions have been of considerable value. Rice and Markley (1924) made an attempt to assign contributions of the various milk components to titratable acidity. One scheme utilizes oxalate to precipitate calcium and rennet to remove the calcium caseinate phosphate micelles (Horst 1947 Ling 1936 Pyne and Ryan 1950). As formulated by Ling, the scheme involves titrations of milk, oxalated milk, rennet whey, and oxalated rennet whey to the phenolphthalein endpoint. From such titrations, Ling calculated that the caseinate contributed about 0.8 mEq of the total titer of 2.2 mEq/100 ml (0.19% lactic acid) in certain milks that he analyzed. These data are consistent with calculations based on the concentrations of phosphate and proteins present (Walstra and Jenness 1984). The casein, serum proteins, colloidal inorganic phosphorus, and dissolved inorganic phosphorus were accounted for by van der Have et al (1979) in their equation relating the titratable acidity of individual cow s milks to the composition. The casein and phosphates account for the major part of the titratable acidity of fresh milk. 

Refs l)E.L.Tague, Casein, Its Preparation, Chemistry and Technical Utilization , Van Nostrand, NY(1926) 2)UUmann 3(1929), 110-15 (not found in new edition) 3)Thorpe 2(1938), 411-17 4)H.Hadert, "Casein and Its Uses , Translated from the Ger, ChemPubgCo, NY(1938) 5)E. Sutermeister F.L.Browne, Casein and Its Industrial Application , ACS Monograph No 30, Reinhold, NY(1939) 6)Kirk Othmer 3(1949), 225 36 7)M.Beau, "LaCasdine , Dunod, Paris (1952) 8)J.R.Spellacy, "Casein, Dried and t Condensed Whey , Lithotype Process Co, San Francisco, Calif(1953) 9)US Military Specification, MIL-C-11532... 

Enzymatic hydrolysis of food proteins yields peptides that are of great interest to the food industry and are utilized for various purposes, e.g., improving the functional properties of foods, parenteral feeding (casein hydrolyzates), or milk protein substitutes in cases of intolerance. 

Phenyl isothiocyanate has also been utilized to analyze small quantities of peptides or short-chain peptides (88) by carrying out sequential degradation with detection by dansylation. Using dansyl-Edman degradation, Leadbeater and Bruce-Ward (60) identified 60 tryptic peptides of/8-casein that had previously been separated by high-voltage paper electrophoresis. 

Indeed the images of casein micelles and submicelles in yogurt are impressive. As pointed out in the discussions with reviewers section of the paper the technique is exhaustive and utilizes a highly sophisticated SEM and therefore is not likely to find wide use. The capability to resolve particulates at the 3 nm size range in the SEM mode is truly noteworthy and this reference represents a step forward in defining new capabilities to address specific questions requiring these higher resolutions. 

Kopra, N., Scholz-Ahrens, K.-E., and Barth, C. 1992. Effect of casein phosphopeptides on utilization of calcium in vitamin D-replete and vitamin D-deficient rats. Milchwissenschaft 47, 488-493. 

Tsuchita, H., Sekiguchi, I., Kuwata, T., Igarashi, C., and Ezawa, I. 1993. The effect of casein phosphopeptides on calcium utilization in young ovariectomized rats. Z. Emdhrungswiss. 32, 121-130. 

Yuan, Y.V. and Kitts, D.D. 1991. Confirmation of calcium absorption and femoral utilization in spontaneously hypertensive rats fed casein phosphopeptide supplemented diets. Nutr. Res. 11, 1257-1272. 

Nutrition Effect of Protein-Bound Methionine Sulfoxide. There is some discrepancy in the results concerning the biological availability of protein-bound methionine sulfoxide. Ellinger and Palmer (71) found that oxidized casein had a lower NPU (Net Protein Utilization) than normal casein. Slump and Schreuder (72) concluded that there was a positive biological availability of peptide-bound methionine sulfoxide. 

Manganese is a nutritionally important trace element for chicks. Dietary energy and protein sources contain very little bioavailable Mn, and these feed ingredients reduce the biopotency of inorganic Mn supplements. This adverse effect is exerted primarily in the intestine as a result of reduced Mn absorption and is mediated by the fiber and/or ash components of the feedstuffs. Gut absorption efficiencies are higher when a phytate-and fiber-free casein-dextrose diet is fed than when a corn-soybean meal diet is fed. Dietary interrelationships exist between Mn and Co and between Mn and Fe. Cobalt increases Mn absorption and may precipitate Mn toxicosis. Excess dietary Mn reduces Fe utilization, but excess Fe does not affect Mn utilization. Eimeria acervulina infection increases Mn absorption. 

Turnover and Utilization. There is little doubt that chicks fed excess levels of Mn deposit this mineral in various body tissues. Halpin (24) investigated the capacity of the chick to remove this Mn from stored deposits and to use it for normal bodily functions. Chicks were fed either 14 or 2000 ppm Mn in a casein-dextrose diet for two weeks (8 to 22 days posthatching). 

This paper draws heavily upon the "Nomenclature Committee Report" ( 1) as well as several recent comprehensive reports that have considered the primary structure and conformation of the casein monomer subunits and how they are assembled into submicel-lar aggregates and casein micelles (2, 3). These basic relationships were utilized to develop additional projections relating to the conformation and functional properties of the major milk proteins, e.g., commercial caseinates and whey protein concentrates in food applications. 

In contrast to the caseins, whey proteins retain their solubility in the pH 4.5-5.0 range, provided they have not been denatured. It is therefore relatively difficult to recover and purify undenatured protein concentrates on a commercial scale. Processes that separate the whey proteins from the low molecular weight, nonprotein components of whey have been used with only moderate success to date (18). Such processes utilize ultrafil-tration/reverse osmosis membrane technology, gel filtration by the basket centrifuge technique, polyvalent ion precipitating agents... 

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