Cheese whey protein recovery

Cheese Whey Protein Recovery. Perhaps the best publicized application for UF is in cheese whey processing. "Cheese whey" is the supernatant liquid produced in the cheese making process after precipitation of casein from milk. There are two types of whey "sweet" whey (minimum pH of 5.6) results when rennet-type enzymes are used to coagulate the casein to form Gouda and Cheddar cheeses ... 

Filtration of small (nano) particles from solvent using a filter with extremely small pores (0.001-0.010 micron) finer than ultrafiltration, not as fine as reverse osmosis. Used for the removal of viruses from plasma protein products. See Yaroshchuk, A.E., Dielectric exclusion of ions from membranes, Adv. Colloid Interface Sci. 85,193-230,2000 Rossano, R., D Elia, A., and Riccio, R, One-step separation from lactose recovery and purification of major cheese-whey proteins by hydroxyapatite — a flexible... 

Membrane-retained components are collectively called concentrate or retentate. Materials permeating the membrane are called filtrate, ultrafiltrate, or permeate. It is the objective of ultrafiltration to recover or concentrate particular species in the retentate (eg, latex concentration, pigment recovery, protein recovery from cheese and casein wheys, and concentration of proteins for biopharmaceuticals) or to produce a purified permeate (eg, sewage treatment, production of sterile water or antibiotics, etc). Diafiltration is a specific ultrafiltration process in which the retentate is further purified or the permeable sohds are extracted further by the addition of water or, in the case of proteins, buffer to the retentate. 

The largest industrial use of ultrafiltration is the recovery of paint from water-soluble coat bases (primers) applied by the wet electrodeposition process (electrocoating) in auto and appliance factories. Many installations of this type are operating around the world. The recovery of proteins in cheese whey (a waste from cheese processing) for dairy applications is the second largest application, where a... 

Even though liquid whey has been successfully commercialized in the form of alcoholic and nonalcoholic beverages, these are still a rarity in most countries. Most whey is converted to whey solids as ingredients for human food or animal feeds by traditional processes such as spray drying, roller drying, concentration to semisolid feed blocks, or production of sweetened condensed whey. Jelen (1979) reported other traditionally established processes including lactose crystallization from untreated or modified whey, production of heat-denatured whey protein concentrate, or recovery of milk fat from whey cheese in whey butter. ... 

The Steffen process, which uses calcium oxide for precipitation of sucrose from molasses, has been applied to the recovery of lactose from cheese whey (Cerbulis 1973). By proper control of the reaction, over 90% of the lactose can be recovered as an insoluble calcium-lactose complex. The addition of ferric chloride in combination with calcium oxide improves lactose yields. Addition of equal volumes of acetone or methanol gives almost complete precipitation of lactose and protein from whey. 

Whey centrifugation at 1000 g during 5 min (process 1) allowed a 20.8% recovery of cheddar cheese whey initial lipids (Table 21.10). The other components, proteins and lactose were precipitated at a lower rate (1.1% and 0.6%, respectively). A 32.1 % whey lipid precipitation was obtained in process 2 consisting of an electroacidification to reach a pH value of 3.7 before the centrifugation step. This represents a 54% increase of precipitation rate in comparison with process 1, with proteins and lactose precipitation levels quite similar (1.9% and 0.9%, respectively). Demineralization step before electroacidification had only small effect on the precipitation level Similar precipitation levels for lipids and lactose were obtained in comparison with process 2 values except for proteins. Conventional electrodialysis allowed an increase of protein precipitation from 1.9% to 3.3% (Table 21.11). 

Microfiltration processing for clarification and defatting of cheese whey, for selective separation and concentration of micellar caseins from milk for various purposes, for fractionation of caseins and their peptides, for recovery of native whey proteins from milk, for gentle sterilization of milk to produce extended shelf fife liquid milk and cheese milk, for fractionation of globular milk fat and its components, for the reduction of microorganisms in cheese brine, and for the removal of colloidal particles in membrane cleaning solutions. 

Ultrafiltration processing for whey proteins concentration and fractionation, for recovery of lactose from milk and whey, for total milk protein concentration for the production of milk protein concentrate (MFC) or nulk protein isolate (MPl), for milk standardization for continuous mechanized manufacture of cheese and other fermented products, and for production of high-solids milk base for dried milk production. 

More specifically, these systems, whether operated in the conventional mode or as rotary units have been successfully utilized in applications such as the recovery of protein and lactose from cheese whey, separation of fermentation products, concentration of fluids foods and juices, manually operable sea water desalinators, recovery of starch from potato processing fluids, and processlng/separatlon of pharmaceutical and chemical mixtures. 

This phenomenon, called reverse osmosis, is used in a number of processes. An important commercial use is in the desalination of seawater or brackish water to produce fresh water. Unlike distillation and freezing processes used to remove solvents, reverse osmosis can operate at ambient temperature without phase change. This process is quite useful for processing of thermally and chemically unstable products. Applications include concentration of fruit juices and milk, recovery of protein and sugar from cheese whey, and concentration of enzymes. 

Ultrafiltration is used in many different processes at the present time. Some of these are separation of oil-water emulsions, concentration of latex particles, processing of blood and plasma, fractionation or separation of proteins, recovery of whey proteins in cheese manufacturing, removal of bacteria and other particles to sterilize wine, and clarification of fruit juices. 

Electrostatic interaction between chitosan and milk fat globule fragment facilitated fat and protein recovery. Fernandez and Fox (Fernandez, Fox, 1997) reported the use of chitosan to remove proteins and peptides from cheese whey. Urea-PAGE (polyacrylamide gel electroplorosis) showed that chitosan gave good fractionation of water-soluble extract at pH 2, 3, and 4. At pH 5, 6, and 7, most of the nitrogen of the water-soluble extract remained soluble in 0.02% chitosan. 

Ultrafiltration is currently dominated by two large apphcations, the recovery of electropaint waste water and the recovery of proteins from dairy wastes. The former application results from the use of solvent-free paints, especially for automobiles. These paints are electrostatically apphed. Any wash water is then processed to recover suspended pigments and other colloidal material. In the dairy industry, cheese whey can be concentrated and purified. In some cases, ultrafiltration concentrates valuable albumins that are lost in conventional processes. 

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