Salt whey

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. 

To a large extent, the utilization of whey and whey byproducts (including salt whey and whey permeate) is a problem of utilizing the milk sugar, lactose. Since the excess lactose produced in the United States each year amounts to more than a billion pounds, one must consider its use in large volume products. One such product is lactose-based polyether-polyol used in the manufacture of low-density rigid polyurethane foams (2). 

Component Fluid Sweet Whey Fluid Acid Whey Salt Whey Whey Permeate... 

Among other applications, this membrane is being used in the treatment of salt whey, a waste stream product of cheese making in which the sodium chloride content is very high (up to 7%). The salt whey protein and lactose can be both concentrated and desalted in a single membrane operation (requires some diafiltration). 

GE-Osmonics (part of GE Water Technologies) commercializes the Desal 5 nanofiltration membranes, used for removal of hardness and other contaminants, alcohol recovery from aqueous solution and removal of salt from salt whey. The membrane has 4 layers, a polyester nonwoven, an asymmetric micro-porous polysulfone and two proprietary thin films, which might be based on sulfonated polysulfone and polypiperazineamide [34]. A comparison between DesaF 5 and NF270 for nanofiltration has been reported by [44] (Tab. 4.3). 

Electro dialysis is used widely to desalinate brackish water, but this is by no means its only significant appHcation. In Japan, which has no readily available natural salt brines, electro dialysis is used to concentrate salt from seawater. The process is also used in the food industry to deionize cheese whey, and in a number of poUution-control appHcations. 

Ultrafiltration. Membranes are used that are capable of selectively passing large molecules (>500 daltons). Pressures of 0.1—1.4 MPa (<200 psi) are exerted over the solution to overcome the osmotic pressure, while providing an adequate dow through the membrane for use. Ultrafiltration (qv) has been particulady successhil for the separation of whey from cheese. It separates protein from lactose and mineral salts, protein being the concentrate. Ultrafiltration is also used to obtain a protein-rich concentrate of skimmed milk from which cheese is made. The whey protein obtained by ultrafiltration is 50—80% protein which can be spray dried. 

Leading Examples Electrodialysis has its greatest use in removing salts from brackish water, where feed salinity is around 0.05-0.5 percent. For producing high-purity water, ED can economically reduce solute levels to extremely low levels as a hybrid process in combination with an ion-exchange bed. ED is not economical for the produc tion of potable water from seawater. Paradoxically, it is also used for the concentration of seawater from 3.5 to 20 percent salt. The concentration of monovalent ions and selective removal of divalent ions from seawater uses special membranes. This process is unique to Japan, where by law it is used to produce essentially all of its domestic table salt. ED is very widely used for deashing whey, where the desalted product is a useful food additive, especially for baby food. 

Ultrafiltration may be distinguished from other membrane operations by example When reverse osmosis is used to process whey, it passes only the water and some of the lactic acid (due to the solubihty of lactic acid in RO membranes). Nanofiltration used on whey will pass most of the sodium salts while retaining the calcium salts and most of the lactose. Microfiltration will pass everything except the particulates and the bacteria. 

Lactoferrin (from human whey). Purified by direct adsorption on cellulose phosphate by batch extraction, then eluted by a stepped salt and pH gradient. [Foley and Bates Anal Biochem 162 296 1987.]... 

Tankwater, Bright dip acid (phosphoric), Cyanide rinse hath, Pickle Liquor, Sodium AJuminate Liquor, N.S.S.C. Liquor, Kraft Liquor, Soda Liquor, Sulfite Liquor, Stillage, Corn Syrup, Gelatin, Salt, Soybean Oil, Steepwater, Sugar, Whey, Mercerizing Caustic, Nylon Salt, Rayon Spin Bath, and Sodium Sulfate. 

Sodium glutamate MSG 1-glutamic acid monosodium salt hydrolyzed vegetable protein utolyzed yeast whey protein... 

See also whey protein monosodium salt. See monosodium glutamate... 

During cheese making, the coagulated milk or curd is used to make cheese while the supernatant whey is a waste product rich in salts, proteins, and lactose. Whey concentration and desalting by UF produce a retentate product that can be used as an animal feed supplement or food additive. The MMV process (Maubois et al., French Patent 2,052,121) involves concentrating the milk by UF after centrifugation to remove the cream and before coagulation to improve yields and reduce disposal costs. 

Milk from cows contains 3.2% protein, about 80% of which is casein. Casein is isolated by a precipitation process from milk, involving heating, rinsing to remove whey, and drying to a powder. The yield is about 3 kg/ 100 kg skim milk. Rennet casein is obtained when the casein is precipitated by chymosin enzyme, also known as rennet, and acid casein is produced when precipitation is accomplished by acidification. Acid casein is usually found in the form of sodium caseinate or calcium caseinate, which are water-soluble salts. Caseinates are made by reacting NaOH or CaOH with a slurry of casein curd or powder and then spray drying (Southward, 2010). 

Karleskind, D., Laye, 1., Halpin, E., and Morr, C. V. (1991). Improving acid production in soy based yogurt by adding cheese whey proteins and mineral salts. J. Food Sci. 56, 999-1001. 

Pharmacia s Q- and S-Sepharose anion- and cation-exchange resins For the anion-exchange process it was found that two step changes, simultaneous in pH and salt concentration were necessary to carry out the anion-exchange separation. A 0.01 M sodium acetate buffer, pH 5.8, was used forthe starting state orfeed loading buffer. After the whey feed was loaded onto the column, one column volume of this... 

W. R. Carper, Molten Salts, in Encyclopedia of Nuclear Magnetic Resonance (D. M. Grant, R. K. Harris eds.), John Whey Sons, New York, 1995. 

In the case of cold-induced aggregation and gelation, two different types of gel microstructure, namely filamentous and particulate (Figure 2.1), have been obtained by adding different concentrations of a ferrous salt to solutions of pre-denatured p-lactoglobulin (the major whey protein). This substantial difference in microstructure turns out to have a major impact on the iron delivery, due to the different sensitivities of the structures to the relevant environmental conditions, such as pH and the presence of digestive enzymes. In particular, the filamentous gel micro-... 

Akhtar, M., Dickinson, E. (2003). Emulsifying properties of whey protein-dextran conjugates at low pH and different salt concentrations. Colloids and Surfaces B Biointerfaces, 31, 125-132. 

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 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. 

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