Caseins, sodium complexes

SYNS CASEIN and CASEINATE SALTS (FCC) CASEIN-SODIUM CASEIN, SODIUM COMPLEX CASEINS, SODIUM COMPLEXES NUTROSE... 

Synonyms cas 9005-46-3 CASEixand caseinate salts casein-sodium casein, sodium complex caseins,... 

See Diethylene tricaseinamide Casein-sodium Casein-sodium complex ... 

Sodium carrageenate Sodium carragenate. See Sodium carrageenan Sodium caseinate CAS 9004-36-3 9005-46-3 Synonyms Casein-sodium Casein-sodium complex Casein sodium salt Caseins, sodium complexes... 

Casein, ammonium salt. See Ammonium caseinate Casein, calcium salt. See Calcium caseinate Casein hydrolysate. See Hydrolyzed casein Casein, potassium salt. See Potassium caseinate Casein-sodium Casein-sodium complex Casein sodium saH. See Sodium caseinate... 

Caseins, potassium complexes. See Potassium caseinate Caseins, sodium complexes. See Sodium caseinate Casseins, calcium complexes. See Calcium caseinate Castor oil. See Castor (Ricinus communis) oil... 

Casein sodium salt. See Sodium caseinate Caseins, potassium complexes. See Potassium caseinate... 

Synonyms Casein, potassium salt Caseins, potassium complexes Definition Potassium salt of casein Properties Off-wh. solid Toxicology TSCA listed Uses Antistat in cosmetics flavoring agent in dairy prods., margarine, frozen custard, fruit sherbets binder emulsifier for low sodium dietetic foods... 

Studies are currently underway in Moscow on the suitability of using sodium caseinate nanoparticles as carriers for phosphatidylcholine (lecithin) containing > 80% unsaturated fatty acids (oleic, linoleic, linolenic). In particular, it has been established that phosphatidylcholine oxidation can be reduced, or effectively eliminated altogether, in dispersed systems containing complexes with the protein (see Figure 2.4). 

On considering the foaming capacity of these systems, we have found a synergistic effect for complexes of sodium caseinate with phosphatidylcholine, i. e., a four-fold increase in the half-life the foam as compared to the pure protein foam in the range of experimental conditions studied (pH 5.5-7.0 ionic strength 0.001-0.01 M). We note also here that pure phosphatidylcholine did not give fine stable foams at all under these same experimental conditions. Thus, it is evident that food-grade sodium caseinate nanoparticles can potentially possess dual functionality in food... 

Figure 6.9 Effect of CITREM concentration on the molecular and thermodynamic parameters of complex protein-surfactant nanoparticles in aqueous medium (phosphate buffer, pH = 7.2, ionic strength = 0.05 M 20 °C) (a) extent of protein association, k = Mwcomplex/Mwprotem (b) structure-sensitive parameter, p (c) second virial coefficient, A2 (rnolal scale) (d) effective charge, ZE (net number n of moles of negative charges per mole of original sodium caseinate nanoparticles existing at pH = 7.2 (Mw = 4xl06 Da)). The indicated cmc value refers to the pure CITREM solution. Reproduced from Semenova et al. (2007) with permission.

In support of the possibility to manipulate foam stability by changing the nature of protein assembly in the presence of surfactant, Table 6.3 shows a correlation between molecular parameters of protein-phospholipid complexes and the visual appearance of foams stabilized by them in solutions of different pH. The data indicate that the foams stabilized by complexes of phospholipid liposomes with sodium caseinate exhibit a dramatic increase in stability as compared to the corresponding pure protein foams. (The phospholipid sample by itself did not make fine stable foams at any of the concentrations investigated). 

Table 6.3 Effect of protein self-assembly, induced by interaction with lecithin, on the stability of foams stabilized by complexes of sodium caseinate (1 % w/v) with soy phospholipids Lipoid S-21 (1(T5 M) (Istarova et al., 2005 Semenova, 2007). Values of Mw and A 2 are presented for the protein with and without surfactant at three pH values. Also shown are photographs of foams recorded 9 minutes following foam preparation. In each of the images the volume of the glass vessel containing die foam is 10 ml. 

Figure 7.16 Dependence on tlie polysaccharide concentration CDS of (a) tlie second virial coefficient A2 and (b) tlie stmcture-sensitive parameter p of complexes of sodium caseinate + dextran sulfate , complexes prepared in bulk solution a, complexes prepared at tlie interface in a protein-stabilized foam , sodium caseinate alone. Reproduced from Semenova et al. (2009) with permission.

Table 7.3 Relationship between molecular parameters (A2, p) of sodium caseinate (0.5 wt%) + dextran sulfate complexes at pH = 6.0 formed in the bulk and at the interface of a protein foam, and the corresponding properties (J43, Q of the bilayer and mixed emulsions (20 vol% oil, 0.5 wt% sodium caseinate) containing 0.1 or 1.0 wt% dextran sulfate (Jourdain et aL, 2008 Semenova et al., 2009).

Jourdain, L., Leser, M.E., Schmitt, C., Michel M., Dickinson, E. (2008). Stability of emulsions containing sodium caseinate and dextran sulfate relationship to complexation in solution. Food Hydrocolloids, 22, 647-659. 

Figure 8.13 Effect of the method of preparation of the complexes of sodium caseinate (CN) + dextian sulfate (DS) on the time dependence of interfacial shear viscosity, r s, and interfacial shear elasticity, Gs (frequency 0.1 s 1) ( ) CN + DS, mixed layer, freshly prepared complexes (O) CN + DS, mixed layer, 24-h-old complexes ( ) CN + DS, bilayer. Aqueous solutions contained 0.5 wt% CN and 1 wt% DS in 20 mM imidazole buffer at pH = 6. Reproduced from Jourdain et al. (2009) with permission.

Cation-exchange columns have been used effectively by some investigators for the fractionation of casein (Annan and Manson 1969 Kim et al 1969 Kopfler et al. 1969 Snoeren et al. 1977 Saito et al 1979). Sulfoethyl-Sephadex was used by Annan and Manson (1969) with formate buffer to fractionate the as-casein complex. Cellulose phosphate, carboxyl-methyl-cellulose (CMC), potassium-K-carrageenan, and sodium Amberlite CG50 columns have also been used to fractionate the caseins (Kim et al. 1969 Kopfler et al. 1969 Snoeren et al 1977). A batch method for the preparation of para-K-casein from rennin-treated whole casein has been developed with CMC Sephadex (Saito et al. 1979). 

Lipase associated with the casein micelles in skim milk is not fully active, but both dilution and the addition of sodium chloride stimulate or restore activity, presumably by dissociating the micelle-lipase complex. Sodium chloride is an inhibitor of lipolysis, but the proper dilution and addition of this salt can elicit maximal activity (Downey and Andrews 1966). 

In the latter part of the 1950s, this author (Hayes, 1960) attempted to repeat the experimentation used by Waksman and Iyer (1932,1933). He exhaustively washed powdered wheat straw with boiling water, then with hot dilute hydrochloric acid, and extracted twice for 5h in an autoclave at 120 °C, each time with a 4% sodium hydroxide solution. The combined filtrates were acidified to pH 4 with hydrochloric acid and the precipitate formed was washed free of chloride and freeze-dried. A ligno-casein complex was formed by reacting three parts of the lignin extract and one part casein in a 0.1 M solution of sodium hydroxide and collecting the precipitate formed when the pH was adjusted to 4. This complex was washed free of chloride and freeze-dried. A 6 1 lignin-protein complex was formed in the same way. 

Proteolytic modification has special importance for the improvement of solubility of proteins. This effect becomes significant even after very limited proteolysis. Hydrolysis of casein to DH of 2 and 6.7% with Staphylococcus aureus V8 protease increased the isoelectric solubility to 25 and 50%, respectively (Chobert et al., 1988a). However, it should be noted that the solubility profiles were not identical, due to a shift of the isoelectric point of the modified proteins. Solubility of a protein hydrolysate depends on the enzyme used (Adler-Nissen, 1986a). Protamex (a Bacillus proteinase complex) hydrolysates of sodium caseinate (DH 9 and 15%) displayed 85-90% solubility between pH 4 and 5 (Slattery and FitzGerald, 1998). 

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