Whey sweet

Whey is the fluid obtained by separatiag the coagulum from cream and/or skim milk, and is a by-product of either caseia or cheese manufacture. The composition of whey is determined by the method of curd formation, curd handling practices, and methods of handling whey as it is separated from the curd. Dried acid whey contains ca 12.5 wt % proteia (total nitrogea x6.38), 11.0 wt % ash, and 59 wt % lactose, whereas sweet whey contains 13.5 wt % proteia, 1.2 wt % fat, 8.4 wt % ash and 74 wt % lactose. The composition varies with the type of acid used (7). 

Whey has been used ia some substitute dairy products but aot as a source of proteia. Whey proteias have beea used ia dairy substitutes only siace the commercialisation of ultrafiltration (qv) technology. Membranes are used that retain proteia and permit water, lactose, and some minerals to pass through as permeate. Proteia coaceatrates are available from both acid and sweet whey and ia coaceatratioas of 35—80 wt % proteia. Whey proteia isolates are commercially available having proteia >90 wt%. The cost of these isolates is too high, however, to make them economical for substitute dairy foods. 

Component, wt % 42% Butteraulk 30% Clotted whey (pH 1.5) 15% Sweet whey Total 100%... 

After the cheese making process the sweet whey is produced, it is further processed by reverse osmosis to increase the solids content from approximately 5.5% (w/w) to... 

Figure 2.15 Schematic representation of plant for the manufacture of crude and refined lactose, from sweet whey.

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. 

Products manufactured from whey only Dried sweet whey 12 74 8.5 1, 2, 3, 4, 5, 6... 

Processes for crystallization of lactose are well established, with production generally limited to a few large plants. Although a variety of cheese wheys and whey ultrafiltrates can be used for lactose production, sweet whey or ultrafiltrates are preferred (Woychik 1982). The crystallization process has three basic steps ... 

Guy, E. J. 1979. Purification of syrups from hydrolyzed lactose in sweet whey permeate. J. Dairy Sci. 62, 384-391. 

Hicks, K. B. Raupp, D. L. and Smith, P. W. 1984. Preparation and purification of lactulose from sweet whey ultrafiltrate. J. Agri. Food Chem. 32, 288-292. 

Leviton, A. and Leighton, A. 1938. Separation of lactose and soluble proteins of whey by alcohol extraction-extraction from spray dried whey powder derived from sweet whey. Ind. Eng. Chem. 30, 1305-1311. 

Component Cow milk Sweet whey Acid whey Unit... 

Boyaval, P. and Corre, C. 1987. Continuous fermentation of sweet whey permeate for propionic acid production in a CSTR with UF recycle. Biotechnol. Lett. 9(11), 801-806. 

Mega Cal calcium with vitamin D, 1 tablet supplied 500 mg calcium and 100 mg vitamin D, derived from egg shells, oyster shells, calcium lactate, calcium gluconate, calcium carbonate, non-fat dried milk, malted milk and dairy sweet whey. Holistic Products Corp. East Rutherford, NJ 07073. 

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

As can be seen from Figure 19.27 skim milk can be fractionated by means of UTP MF (0.1 pm), in combination with an UF diafiltration step, in its two main protein fractions, i.e. native casein micelles and native whey proteins since no heat treatment step was required to separate the proteins. The MF permeate can be considered a sort of sweet whey, however, without containing the caseinomacropeptide (CMP). This MF permeate can be further concentrated to obtain a WPC product. The... 

Plock, J., Spiegel, T., and Kessler, H.G. (1997). Reaction kinetics of the thermal denaturation of whey protein in sweet whey concentrated by evaporation. Milchwissenschaft 53, 327-331. 

Concentration of whev proteins. As mentioned earlier, microfiltration can be used to remove bacterias. In addition, they are capable of separating phospholipids, fats and casein fines of sweet whey or sour (acidified) whey. Ultrafiltration of whey has been well proven to provide an array of protein products of diverse compositions and properties. Inorganic membrane filtration can be used at different stages of the process to make whey protein concentrates (WPC) in powder form with a protein content reaching 50%. 

Separation of lactic and propionic acids. The lactose fraction in the sweet whey permeate from cheese whey ultrafiltration can be fermented to produce lactic acid. In conjunction with the fermentation step, inorganic membranes have been tested in a continuous process to separate the lactic acid. This approach improves the productivity and reduces energy consumption compared to a conventional fermentation process. In addition, it produces a cell-free product. In a conventional process, some cells, although immobilized, are often detached and released to the product Zirconia membranes with a MWCX) of 20,000 daltons were operated at 42 C and a crossflow velocity of 2-5 m/s for this purpose [Boyaval et al., 1987]. The resulting permeate flux is 12-16 L/hr-m. To... 

Propionic acid and its derivatives are used in food, perfume and plastic applications. Traditional processes for making this compound, however, have limited productivity due to the low growth rate of the propionic bacteria and the inhibitory effect of the acid on the fermentation. The cheese whey permeate can be an inexpensive source of propionic acid. Propionic acids can be produced by fermentation of sweet whey permeate in a stirred tank reactor with cells separated from the medium and recycled back to the reactor by an ultrafiltration Z1O2 membrane on a carbon support [Boyaval and Corre, 1987]. This arrangement reduces the propionic acid concentration and increases the... 

Tanny et al. [71] proposed CFMF as a potential solution to the fat removal problem in whey. Using 1.2 p,m pore size MF membrane to clarify sweet cheese whey, Merin et al. [68] observed a permeate that was totally free of fat, while containing aU the other whey components. Compared to the centrifuge-separated and nontreated whey, Merin et al. [68] reported 30% increase in permeation flux when the MF permeate was used as a feed stream in UF to produce WPC. They explained that this is probably due to the absence of small fat globules and casein fines in the MF permeate, which were suggested as major contributors to permeation resistance in the UF of sweet whey. The same group observed reduction of bacteria in the MF permeate by 1 to 2 orders of magnimde. 

A major emphasis in the utilization of MF in the dairy industry that is of relevance to cheesemaking is changing the casein to whey protein ratio or the casein to fat ratio in mUk fractions [91]. MF of whole or skim mUk produces a retentate that is rich in native micellar casein, which improves the cheesemaking process, and a crystal clear and sterile permeate with composition close to that of sweet whey but with greater amount of native whey proteins that is suitable for direct manufacmre of whey protein isolate [8,52,92-95]. In processing skim mUk using MF membranes of 0.2 p,m pore size or smaller, the permeation of... 

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