Lactose cheese making

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. 

Although < 12% of the species of yeast use lactose (see Table III), this utilization is of commercial interest, as /3-D-galactosidase (EC 3.2.1.23) from yeasts may be used to lower the lactose content of dairy products, such as whey from cheese-making (for example, see Ref. 359) or milk itself.380... 

Lactose is the characteristic carbohydrate of milk, averaging about 4.9% for fluid whole cow s milk and 4.8% for sheep and goat s milk. The commercial source of lactose today is almost exclusively sweet whey, a by-product of cheese making. Details of its production are given in Chapter 6. 

Whey is the liquid obtained by separating the coagulum from milk, cream, and/or skim milk in cheese making. Whey obtained from the process in which a significant amount of lactose is converted to lactic acid or obtained from the curd formed by direct acidification of milk is known as acid-type Whey. Whey obtained from the process in which there is insignificant conversion of lactose to lactic acid is known as sweet-type Whey. The acidity of Whey may be adjusted by the addition of safe and suitable pH-adjusting ingredients. The final product is pasteurized and is available as a liquid or dry product. 

Whey is the by-product of cheese-making. The traditional form of whey in confectionery is whey powder, which has been used as an ingredient in some toffees. Apart from this example, whey has not been much used in sugar confectionery. The reasons for this are hard to see, except that in toffees the flavours imparted by whey are not that pleasant. As the major ingredient is lactose this places another restriction on its use - lactose has its limited solubility compared with other sugars, when used to excess it imparts the unpleasant metallic taste, and it is not tolerated in the diets of certain consumers. 

There are other markets for concentrated milk besides cheese making. Condensed milk or dietary milks (without lactose or salts) can be easily prepared with UF. The solids concentration can be increased to well over 20% but with large increases in viscosity (over 30,000 cp). 

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). 

Lactose is synthesized in the mammary (milk-producing) glands of mammals. The milk of such animals contains an enzyme called lactose synthetase, which acts on the compound uridine diphosphate D-galactose to produce lactose. The compound is obtained commercially from whey, a byproduct of the cheese-making process. The solids in whey contain about 70 percent lactose by weight. These solids are... 

CAS 92129-90-3 Synonyms Lacto-serum Definition Liq. substance obtained by separating coagulum from milk, cream, or skim milk in cheesemaking as sweet or acid whey, cone, whey, or dried whey contains typically 5% lactose, 1% protein, 1% fats, salts, lactic acid Uses Food ingred. in cheese-making animal feed ingred. 

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. 

Cheese making may raise or lower the amount of calcium in 100-Calorie (kcal) portions of the product compared to the original milk because variable amounts of calcium, phosphorus, protein, and lactose are lost in the whey, depending upon whether the milk is clotted with rennet, or with acid alone. Table M-26 shows how the contents of calories, calcium, and phosphorus vary tetween milk and several types of popular cheeses. 

After most types of cheese are manufactured, about 50% of the milk solids (most of the lactose and lactalbumin) remain in the whey. Cheese-like products can be made from these residual solids. One of the two methods commonly used to make these whey cheeses consists of contentrating the whey through evaporation with heat to obtain a mass with a firm, sugary consistency that, when cooled, forms a cheese (Primost and Ghetost). The other method is employed in the manufacture of Ricotta cheese. 

Although whey protein products have several food uses, the lactose contained in the permeate is less valuable, and many plants discharge the permeate to a biological wastewater treatment plant. A few plants recover lactose as dry lactose sugar, as shown in Figure 6.23. Some plants also ferment the lactose concentrate to make ethanol. An introduction to membrane ultrafiltration in cheese production is given by Kosikowski [26],... 

Part of the process to make cheese involves the flocculation of an electrostatically stabilized colloidal O/W emulsion of oil droplets coated with milk casein. The flocculation is caused by the addition of a salt, leading to the formation of networks which eventually gel. The other part of the process involves reaction with an enzyme (such as rennet), an acid (such as lactic acid), and possibly heat, pressure and microorganisms, to help with the ripening [811]. The final aggregates (curd) trap much of the fat and some of the water and lactose. The remaining liquid is the whey, much of which readily separates out from the curd. Adding heat to the curd (-38 °C) helps to further separate out the whey and convert the curd from a suspension to an elastic solid. There are about 20 different basic kinds of cheese, with nearly 1000 types and regional names. Potter provides some classification [811]. 

Several years ago the enzyme industry looked at the cheese industry and saw lactase as a big opportunity. Besides the lactose crystallization problem in frozen and concentrated milk products, the enzyme industry saw another potentially big profit application. Over half of the cheese whey produced in making cheese is diverted to waste treatment or waste disposal systems rather than being processed for food and feed use. Upgrading cheese whey became the hot development item for the enzyme industry. 

Aside from improved yield, the use of UF pre-cheese results in the improvement of product taste and texture compared to cheese produced by conventional methods because of the reduction of lactose content, controlled acidification rate, and increase in the water-holding capacity of the product due to the incorporation of whey, which makes for softer product [25,73,79]. Lucisano et al. [77] noted an enhanced rennet-induced clotting time of UF-concentrated irulk as pH is lowered from its natural pH level. 

Lactose makes up about 5% of human milk and of cow s milk. It is obtained commercially as a by-product of cheese manufacture, being found in the whey, the aqueous solution that remains after the milk proteins have been coagulated. Milk sours when lactose is converted into lactic acid (sour, like all acids) by bacterial action (e.g., by Lactobacillus bulgaricus),... 

Proteins and water. Clarified butter is made by melting regular butter at a low temperature. Three layers will form the top frothy layer contains the proteins from milk (casein, used to make cheese) the middle layer is water with dissolved milk sugars, like lactose the bottom layer is pure butterfat or milkfat, which is also known as clarified butter. You can instead heat butter at a low temperature for a long time to remove the water by evaporation, and then decant or filter the butterfat. Clarified butter contains almost no proteins, so it has a very long shelf life, and no lactose, so people who are lactose-intolerant can eat it. 

The application of whey, a main by-product in the manufacturing of dairy products and cheese, has been widely explored in the production of PHA. Whey serves as an excellent carbon and energy source as lactose makes up 70% of the total dry matter. Whey retentate is mainly composed of a-lactalbumin and P-lactoglobulin proteins which can be employed as a nitrogen source for the enhanced cultivation of microbial PHA-producing strains [2, 34, 35]. However, the inability of some PHA-producing strains to utilise raw whey has... 

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. 

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