Dairy industry cheese manufacturing

In order to offer the consumer a greater variety of dairy products other then milk, UHT milk, sour milk products, cream, butter or cheese, the dairy industry has developed a variety of flavoured dairy products and later in the sixties, dairy products containing (fruit) preparations. The latter category originated from a close cooperation between the dairy industry, fruit manufacturers and flavour houses. Fruit juice processing companies, marmalade manufacturers and also flavour houses established departments for (fruit) preparations which resulted in a great variety of preparations. 

Traditionally, dairy products (cheese, fermented milks, butter) were produced on an artisanal level, as is still the case in underdeveloped regions and to some extent in highly developed dairying countries. Industrialization commenced during the nineteenth century and dairy manufacturing is now a well-organized industry. One of the features of the past few decades has... 

Principal micelle characteristics. The structure of the casein micelles has attracted the attention of scientists for a considerable time. Knowledge of micelle structure is important because the stability and behaviour of the micelles are central to many dairy processing operations, e.g. cheese manufacture, stability of sterilized, sweetened-condensed and reconstituted milks and frozen products. Without knowledge of the structure and properties of the casein micelle, attempts to solve many technological problems faced by the dairy industry will be empirical and not generally applicable. From the academic viewpoint, the casein micelle presents an interesting and complex problem in protein quaternary structure. 

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... 

Researchers in both industry and academia have employed immobilized enzymes as biocatalysts. Immobilization usually involves attaching enzymes to solid supports and packing the supports in a tube through which liquid flows. One application has involved conversion of the lactose in dairy fluids to glucose and galactose, which would permit conversion of the whey produced in cheese manufacture to useful by-products. By averaging over the void spaces between solid particles and the particles themselves, one can obtain an effective rate expression per unit volume of the bed of biocatalyst. The rate expression is... 

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. 

Membrane separation technology is well developed in the dairy industry. In particular, the largest applications are related to the use of UF in the fractionation of cheese whey and pre-concentration of milk for cheese manufacture. RO is mainly used for whey concentration and the membrane area has stabilized around 60 000 m (Daufin et al., 2001). MF is able to retain, partially or totally, particles such as microorganisms, casein micelles and fat globules providing longer shelf life than pasteurization. It can be used as pre-treatment of skim nfilk for the production of raw milk cheeses and the reduction of spores in add cheese milk. NF, due to its intermediate... 

Successful applications of integrated membrane operations in the dairy industry are related to the processing of cheese whey. Whey is a liquid fraction produced in the manufacturing of cheese containing a low solids content (5-6% of total solids) represented by approximately 0.7% protein, 4.3% lactose, 0.5% ash and 0.05% fats. The lactose/protein ratio makes its reuse difficult. Further, the biological oxygen demand (BOD) is between 30 000 and 50 000 ppm, creating severe disposal problems. 

Reverse osmosis is used as a concentration step particularly in the food industry (concentration of fruit juice, sugar, coffee), the galvanic industry (concentration of waste streams) and the dairy industry (concentration of milk prior to cheese manufacture). 

Food preservatives are yet another product of industrial fermentation. Organic acids, particularly lactic and citric acids, are extensively used as food preservatives. Some of these preservatives (such as citric acid) are used as flavoring agents. A mixture of two bacterial species (Lactobacillus and Streptococcus) is usually used for industrial production of lactic acid. The mold Asper Uus niger is used for citric acid manufacturing. Another common preservative is the protein nisin. Nisin is produced via fermentation by the bacterium Lactococcus lactis. It is employed in the dairy industry especially for production of processed cheese. 

Fats and oils are important food constituents. Their nutritional, chemical, and physical properties are influenced by the position of fatty adds, their chain length, and the degree of unsaturation. Usually, lipases are used to obtain modified fats with nutritionally improved properties and they provide high value fats such as cocoa butter that contains palmitic and stearic acids. Commercial lipases are mainly employed in the dairy industry for flavor enhancement in cheese (Mase et al., 2010 Omar et al., 1986), the acceleration of cheese ripening (Fox et al., 1996 Kheadr et al., 2002), the manufacture of cheeselike products, and the Upolysis of butterfat and cream (Purko et al., 1952 Seitz, 1974). Lipases release short-chain fatty acids that develop a tangy flavor and medium chain fatty acids that give a soapy taste to the end product (Sharma et al., 2011). 

Proteases have found practical application in various food and other technologies for instance, rennin is used in the dairy industry for the manufacture of hard cheeses, while plant proteases, such as papain, are employed in the prevention of protein hazes in beer. 

Remarks Type strain of the genus Lactococcus, starter culture in the dairy industry, especially in the cheese manufacture, produced bactaiodn nisin, type of species of the genus ... 

The ultrafiltration of milk using polysulphone or polyethersulphone type membranes has a number of applications. The ultrafiltration of milk on farms as a means of reducing refrigeration and transport costs, and the production of speciality milk-based beverages are attractive uses. Cheese manufacture using ultraliltration is another area where the use of membrane filtration is becoming more widespread in the dairy industry. 

In the dairy industry, lipases are used in the hydrolysis of milk fat. Applications include flavor enhancement of cheeses, acceleration of cheese ripening, manufacture of cheeselike products, and lipolysis of butterfat and cream. Sources of lipases for cheese enhancement are the pancreatic glands or pregastric tissues of lamb, calf, or kid. Each pregastric lipase leads to its own characteristic flavor pattern, and these enzymes are essential in the production of quality cheeses such as Romano and provolone [15]. Pregastric lipases have also been used for the treatment of calf diarrhea or scours [15] and have potential for the treatment of malabsorption syndrome in children. 

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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