Dairy industry whey proteins, concentration

Membrane operations have been extensively used in the food industry because they require less manpower, are more efficient, and have a shorter processing time than traditional separation techniqnes, so operational costs are considerably lower than traditional processes [105], For instance, membrane separation processes to clarify and concentrate liquids are less costly than conventional filtration and vacuum evaporation, justifying their application in this field [106]. The primary applications of membranes in the food industry are in the beverage (wine, beer, fruit juices, etc.) and dairy (whey protein concentration, milk protein standardization, etc.), processing industries in the processing of egg prodncts, to a lesser extent, and in water purification. 

The concept of coupling reaction with membrane separation has been applied to biological processes since the seventies. Membrane bioreactors (MBR) have been extensively studied, and today many are in industrial use worldwide. MBR development was a natural outcome of the extensive utilization membranes had found in the food and pharmaceutical industries. The dairy industry, in particular, has been a pioneer in the use of microfiltra-tion (MF), ultrafiltration (UF), nanofiltration (NF), and reverse osmosis (RO) membranes. Applications include the processing of various natural fluids (milk, blood, fruit juices, etc.), the concentration of proteins from milk, and the separation of whey fractions, including lactose, proteins, minerals, and fats. These processes are typically performed at low temperature and pressure conditions making use of commercial membranes. 

Proteinaceous material such as horn, feather, nail, hair, and cheese whey occur in nature as waste and can be converted, by proteases, into liquid concentrates or dry solids with high protein content and of nutritional value for food and feed. Thus, proteases provide potential application for the management of residues from various food processing industries such as poultry and cattle slaughterhouses and fishing and dairy industries [5, 6],... 

Cheese whey is an important by-product from the cheese manufacturing industry. Typically, 100 g of milk yields 10 g of cheese and 90 g of liquid whey. Cheese whey contains about 4.5-5% lactose, 0.6-0.8% soluble proteins, 0.4-0.5% (w/v) lipids, and varying concentrations of mineral salts [1]. Cheese whey disposal has long been a problem for the dairy industry. Most medium and small cheese producers still dispose of their whey or whey... 

Major UF food applications are in the dairy industry [18, 26, 31]. Dairy apphcations have the largest share of membrane capacity in the world with apphcations in whey processing — treatment of cheese whey for recovering milk proteins — and cheese-making. Membrane systems are also used for the production of whole and skim milk concentrates and in the manufacture of lactose-reduced milk products. 

The earhest application of membrane processes in the food industry and one of the largest is in the dairy industry where it is used for (a) the pre-concentration of milk for cheese manufacture and (b) the fractionation of cheese whey. Milk is a complex liquid consisting of 12.5 wt% total solids, 3.3% protein, 3.5% fat, 4.9% lactose and 0.7% ash. RO of cheese whey was commercialised in 1971, and the first UF/RO plant for fractionating cottage cheese was commercialised in 1972. By 1996 approximately 80,000 m RO and 240,000 m UF membrane area was installed for dairy processing [22], of which whey processing constituted 75%. In 1984 NF was introduced for simultaneous concentration and desalination. 

Ultraflltration is also used to fractionate and concentrate proteins from potato processing wastewaters. Other protein wheys can be processed by reverse osmosis. Electrodialysis is used for a number of applications in the food and beverage industry, including deionization or deacidification of fruit juices, wines and, in the dairy industry, milk and whey. It often competes directly with ion exchange processes. 

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. 

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. 

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