Emulsifier casein

The emulsifier casein adsorbs to the interface between the oil and water. 

Shepherd, R., Robertson, A., Ofman, D. (2000). Dairy glycoconjugate emulsifiers casein-maltodextrins. Food Hydrocolloids, 14, 281-286. 

R. Shepherd, A. Robertson, and D. Ofman, Dairy glycoconjugate emulsifiers Casein-maltodextrins, Food Hydrocoil., 14 (2000) 281-286. 

From Diaz et al. (2003). Emulsion was prepared with 5% corn oil and 95% 10 mM imidazole-acetate buffer (pH 7.0), using 17 mM Brij 35 (polyoxyethylene lauryl ether) as emulsifier. Casein hydrolysates (91 P/N, ug/mg) were obtained by trypsin hydrolysis of casein (52 P/N /tg/mg), and 86% enriched caseinophophopeptides (237 P/N /.iglmg) were prepared by precipitation of casein hydrolysates with CaClj and ethanol. 

Most commercial aluminum formate is monobasic aluminum diformate because of the difficulties involved in triformate preparation. The main appHcation is in textile waterproofing. Aluminum formate reacts with casein to form a water-soluble complex, which can emulsify paraffin and certain other waxes. Fabrics immersed in these emulsions are rendered water repellent (26—28). 

In addition to their nutrient value, casein proteins have many other uses. They are good emulsifiers, helping fats to stay suspended in water-based products such as milkshakes, coffee creamers, and ice creams. They are used as binders in processed meats (lunch meats, sausages, etc.). 

Calcium caseinate and butter oil have been extruded directly at 50-60% moisture levels to obtain a cheese analog with no surface water or fat (Cheftel et ah, 1992). The fat emulsification and melting ability increased with screw speed or barrel temperature. The texture of the extmded analogs was similar to those obtained by batch cooking and was affected by pH (Cheftel et ah, 1992) and emulsifying salts (Cavalier-Salou and Cheftel, 1991). The product can be used as adjimcts for hamburger, pizza, and sauces. 

Cavalier-Salou, C. and Cheftel, J. C. (1991). Emulsifying salts influence on characteristics of cheese analogs from calcium caseinate. /. Food Sci. 56, 1542-1547. 

Reconstituted milks with natural milk fat globules (CREAM) or emulsified milk fat droplets stabilized by jS-casein (BCAS), /i-lactoglobulin 5g/L (BLG5), skim milk proteins (MP). 

We now look more closely at the structure of casein. It is a long molecule with different ends one end is polar and the other is nonpolar. In milk, the polar group (ending with a phosphate group) is positioned to face the polar water, and the non-polar end faces the oil. In effect, each particle of oil has a double coating the inner layer is the non-polar end of the casein emulsifier, and the outer layer is a sheath of polar phosphate groups. 

But we must appreciate how the phosphate group acts much like the anion from a weak acid (see Chapter 6), so its exact composition will depend on the pH of solution. The pH of cow s or human milk is about 7 (see Table 6.4). If the pH decreases much below about 6 (e.g. by adding an acid in the form of orange juice), the phosphates become protonated. The emulsifying properties of casein cease as soon as its structure changes, causing the milk to separate. 

Ice cream serves as a wonderful (and tasty) example of a complex, dynamically heterogeneous food system. A typical ice cream mix contains milk or cream (water, lactose, casein and whey proteins, lipids, vitamins, and minerals), sucrose, stabilizers and emulsifiers, and some type of flavor (e.g., vanilla). After the ingredients are combined, the mix is pasteurized and homogenized. Homogenization creates an oil-in-water emulsion, consisting of millions of tiny droplets of milk fat dispersed in the water phase, each surrounded by a layer of proteins and emulsifiers. The sucrose is dissolved in... 

Uses Stabilizing rubber latex solvent for albumin, casein, shellac, and sulfur neutralizing oils in antifreeze as a corrosion inhibitor emulsifier adhesives textile lubricants fungicides manufacturing chelating agents such as EOT A (ethylenediaminetetraacetic acid) dimethylol-ethylene-urea resins organic synthesis. 

Uses Solvent for waxes, casein, dyes, and resins manufacture of rubber additives, various pharmaceuticals, paper chemicals, plasticizers, corrosion inhibitors, emulsifiers, pesticides solvent optical brightener for detergents hair conditioners additive to boiler water preservation of book paper ingredient in various automotive products including brake cleaners and waxes organic synthesis. 

Sanchez, C.C., Rodriguez Patino, J.M. (2005). Interfacial, foaming and emulsifying characteristics of sodium caseinate as influenced by protein concentration in solution. Food Hydrocolloids, 19, 407 116. 

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 emulsification properties of NFDM were slightly better than for caseinate at all protein levels. However. NFDM exhibited lowest emulsification properties at pH 10.4 and highest emulsification at pH 5.6, which was directly opposite the results with caseinate. Thus, the molecular state of caseins, whether in the. micellar or soluble complex form is important in determining their functionality as an emulsifier. 

Whey protein concentrates (WPC), which are relatively new forms of milk protein products available for emulsification uses, have also been studied (4,28,29). WPC products prepared by gel filtration, ultrafiltration, metaphosphate precipitation and carboxymethyl cellulose precipitation all exhibited inferior emulsification properties compared to caseinate, both in model systems and in a simulated whipped topping formulation (2. However, additional work is proceeding on this topic and it is expected that WPC will be found to be capable of providing reasonable functionality in the emulsification area, especially if proper processing conditions are followed to minimize protein denaturation during their production. Such adverse effects on the functionality of WPC are undoubtedly due to their Irreversible interaction during heating processes which impair their ability to dissociate and unfold at the emulsion interface in order to function as an emulsifier (22). 

Figure 9. Emulsification properties of sodium caseinate in the absence of chemical emulsifiers (26)...

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