Caseinate salts, production

Imitation milk—Imitation milks purport to substitute for and resemble milk. These products usually contain water, corn syrup solids, sugar, vegetable fat (coconut, soybean, cottonseed), and protein from soybean, fish, sodium caseinate, or other sources. Although imitation fluid milks do not contain dairy products as such, they may contain derivatives of milk such as casein, salts of casein, milk proteins other than casein, whey, and lactose. Sometimes vitamins A and/or D are added. Ingredient composition, and hence nutrient composition, vary widely. The American Academy of Pediatrics considers imitation milk products inappropriate for feeding infants and young children. 

Fig. 3. Schematic process flow diagram for an imitation cheese product having the following formulation dry ingredients, calcium caseinate (or rennet casein), 24.5 wt % tapioca flour, 3.0 wt % salt, 2.16 wt % adipic acid, 0.6 wt % vitamins and minerals, 0.1 wt % sorbic acid (mold inhibitor), 0.5 wt % fat—color blend, soybean oil hydrogenated to a Wiley melting point of 36°C, 21.3 wt % lactylated monoglycerides, 0.05 wt % red-orange coloring, 0.01 wt...

Whey concentration, both of whole whey and ultrafiltration permeate, is practiced successfully, but the solubility of lactose hmits the practical concentration of whey to about 20 percent total sohds, about a 4x concentration fac tor. (Membranes do not tolerate sohds forming on their surface.) Nanofiltration is used to soften water and clean up streams where complete removal of monovalent ions is either unnecessary or undesirable. Because of the ionic character of most NF membranes, they reject polyvalent ions much more readily than monovalent ions. NF is used to treat salt whey, the whey expressed after NaCl is added to curd. Nanofiltration permits the NaCl to permeate while retaining the other whey components, which may then be blended with ordinaiy whey. NF is also used to deacidify whey produced by the addition of HCl to milk in the production of casein. 

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. 

Regenerated proteins from casein (lanital), peanuts (ardil), soybeans (aralac), and zine (vicara) are used as specialty fibers. Regenerated and modified cellulose products, including acetate, are still widely used today and the production of fibers is similar to that described above for synthetic fiber production. Most regenerated cellulose (rayon) is produced by the viscose process where an aqueous solution of the sodium salt of cellulose xanthate is precipitated in an acid bath. The relatively weak fibers produced by this wet spinning process are stretched to produce strong rayon. 

The properties of many dairy products, in fact their very existence, depend on the properties of milk proteins, although the fat, lactose and especially the salts, exert very significant modifying influences. Casein products are almost exclusively milk protein while the production of most cheese varieties is initiated through the specific modification of proteins by proteolytic enzymes or isoelectric precipitation. The high heat treatments to which many milk products are subjected are possible only because of the exceptionally high heat stability of the principal milk proteins, the caseins. 

Casein is very stable to high temperatures milk may be heated at its natural pH (c. 6.7) at 100°C for 24 h without coagulation and it withstands heating at 140°C for up to 20 min. Such severe heat treatments cause many changes in milk, e.g. production of acids from lactose resulting in a decrease in pH and changes in the salt balance, which eventually cause the precipitation of casein. The whey proteins, on the... 

The inorganic colloidal calcium phosphate associated with casein in normal milk dissolves on acidification of milk to pH 4.6 so that if sufficient time is allowed for solution, isoelectric casein is essentially free of calcium phosphate. In the laboratory, best results are obtained by acidifying skim milk to pH 4.6 at 2°C, holding for about 30 min and then warming to 30-35°C. The fine precipitate formed at 2°C allows time for the colloidal calcium phosphate to dissolve (Chapter 5). A moderately dilute acid (1 M) is preferred, since concentrated acid may cause localized coagulation. Acid production by a bacterial culture occurs slowly and allows time for colloidal calcium phosphate to dissolve. The casein is recovered by filtration or centrifugation and washed repeatedly with water to free the casein of lactose and salts. Thorough removal of lactose is essential since even traces of... 

The procedure used for the industrial production of acid (isoelectric) casein is essentially the same as that used on a laboratory scale, except for many technological differences (section 4.15.1).The whey proteins may be recovered from the whey by salting out, dialysis or ultrafiltration. 

Raw milk is a unique agricultural commodity. It contains emulsified globular lipids and colloidally dispersed proteins that may be easily modified, concentrated, or separated in relatively pure form from lactose and various salts that are in true solution. With these physical-chemical properties, an array of milk products and dairy-derived functional food ingredients has been developed and manufactured. Some, like cheese, butter, and certain fermented dairy foods, were developed in antiquity. Other dairy foods, like nonfat dry milk, ice cream, casein, and whey derivatives, are relatively recent products of science and technology. This chapter describes and explains the composition of traditional milk products, as well as that of some of the more recently developed or modified milk products designed to be competitive in the modern food industry. 

CASEIN. [CAS 9005-46-3], Casein is the phosplioprotein uf fteslt milk the rennin-coagulaled product is sometimes called paracasein. British nomenclature terms the casein of fresh milk caseinogen and the coagulated product casein. As it exists in milk it is probably a salt of calcium. 

The crystallization of lactose in frozen concentrated milk has been associated with a denaluration of casein which ultimately appears as a gel structure in the thawed product. Gelation in frozen milk can be retarded by enzymic hydrolysis of pan ol the lactose before freezing or by addilion of a polyphosphate salt. 

This is formed of the nitrogenous substances (casein, albumin) and fats contained in milk, separated by coagulation (by rennet or by acidification). As a result of special fermentations which occur during the maturation of the cheese, these give rise to soluble albuminoid substances (albumoses, peptones, etc.), amino-adds (phenylaminopropionic add, tyrosine, leucine, etc.), ammoniacal products, fatty adds (lactic, propionic, caproie), etc. Cheese also contains water and mineral salts, including added sodium chloride. 

The interest in mineral fortification of milk for the production of milks with higher nutritional value is a challenge. This is because the introduction of minerals upsets the mineral-protein equilibria in milk which will affect their stability. Philippe et al. (2004) showed that supplementation of skim milk with calcium gluconate, calcium lactate, or calcium chloride (up to 16 mmole added Ca/kg) decreased the heat stability. The addition of MgCl2 or FeCla (at a level of 8 mmole/kg) also reduced the heat stability of casein micelles (Philippe et al., 2005). However, by manipulating the mineral equilibria of milk with the use of a combination of soluble calcium salts and orthophosphates, it is possible to produce milks (with up to 20 mmole added Ca/kg) that are stable to heating (Williams et al., 2005). O Kennedy et al. (2001) showed that denatured whey proteins could be used as a carrier for calcium phosphate and further that adequate heat stability at 130 °C of whey protein-calcium phosphate suspensions could be achieved by appropriate adjustment of pH. 

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