Cheddar cheese whey

Pearce, R.J. 1983. Thermal separation of 3-lactoglobulin and (3-lactalbumin in bovine cheddar cheese whey. Aust. J. Dairy Technol. 38, 144-149. 

Recently, Lin et al. [184] used EDBM technology for acidification and decreasing the ionic strength of a fresh cheddar cheese whey. In this study, EDBM process was carried out with or without preliminary decrease of whey mineral salts content by conventional electrodialysis to obtain precipitates with high level of lipids (Figure 21.36). After centrifugation of the treated whey, composition of floes and precipitation yields was determined. 

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). 

FIGURE 21.36 Cheddar cheese whey treatment hy conventional electrodialysis and EDBM before final centrifugation. 

Lin TSF, Angers P, and Bazinet L. Precipitation of cheddar cheese whey lipids by electrochemical acidification. J. Agric. Food Chem. 2005 53 5635-5639. 

Smith and MacBean (22) applied the pretreatments developed by Hayes et al. (21) to the reverse osmosis of HCl casein and Cheddar cheese wheys, but found that an increase in fouling occurred com-... 

Savant V.D., Torres J.A., Chitosan-based coagulating agents for treatment of cheddar cheese whey, Biotechnol. Prog., 16, 2000, 1091-1097. 

M. pusillus var. Lindt protease has given satisfactory results as a chymosin substitute in the manufacture of a number of cheese varieties, but not all varieties of M. pusillus var. Lindt are capable of producing acceptable cheese (Babel and Somkuti 1968). The clotting activity of M. pusillus var. Lindt protease is more sensitive to pH changes between 6.4 and 6.8 than chymosin, but is much less sensitive than that of porcine pepsin (Richardson et al 1967). The same authors reported that CaCL added to milk affected the clotting activity of M. pusillus var. Lindt rennet more than it did that of chymosin rennet. They also reported that this rennet was more stable than chymosin between pH 4.75 and 6.25. M. pusillus var. Lindt rennet is not destroyed during the manufacture of Cheddar cheese, although less than 2% of the enzyme added to the milk remains in the curd. Nearly all of it is found in the whey (Holmes et al. 1977). Mickelsen and Fish (1970) found M. pusillus var. Lindt rennet to be much less proteolytic than E. parasitica rennet but more proteolytic than chymosin rennet on whole casein, a8-casein and /3-casein at pH 6.65. 

M. miehei rennet is the most heat stable of all the commonly used milk-clotting enzymes (Thunell et al 1979). None is destroyed during Cheddar cheese manufacture although, like M. pusillus var. Lindt rennet, less than 2% remains active in the cheese (Harper and Lee 1975 Holmes et al. 1977). It remains active in the whey and is concentrated in condensed whey products. 

Combined or single effects of heating and acid production by the starter bacteria increase whey syneresis and establish moisture levels for a given variety of cheese. Almost 96% of the moisture lost in Cheddar cheese during cooking occurs in the first 30 min (Lawrence 1959). A comprehensive review of syneresis has been written by Walstra et al. (1985). 

The other major casein in cheese is /3-casein, but it is generally not hydrolyzed by rennet in low-pH cheeses. Alkaline milk protease (plas-min) plays the major role in the hydrolysis of /3-casein (Richardson and Pearce 1981). The plasmin level in cheese is related to the pH of the curd at whey drainage, since plasmin dissociates from casein micelles as the pH is decreased. Richardson and Pearce (1981) found two or three times more plasmin activity in Swiss cheese than in Cheddar cheese. Swiss cheese curds are drained at pH 6.4 or higher, while Cheddar cheese curds are drained at pH 6.3 or lower. Proteolysis of /3-casein is significantly inhibited by 5% sodium chloride. The inhibitory influence of sodium chloride is most likely due to alteration of /3-casein or a reduction in the attractive forces between enzyme and substrate (Fox and Walley 1971). 

The cheddared cheese curd is milled into thin strips, salted, placed in cheese hoops, and pressed overnight to expel additional whey and fuse and curd strips together. The pressed cheese is then removed from the hoops and coated with wax or wrapped in a plastic film. 

Improvement of membrane separation technology has resulted in the isolation of MFGM-enriched material from commercially available products. A phospholipid-rich fraction can be extracted from whey (Boyd et al., 1999) and buttermilk (Sachedva and Buchheim, 1997) with a reported yield of 0.25 g of phospholipids/g of protein in buttermilk (Sachdeva and Buchheim, 1997). Microfiltration of whey derived from the Cheddar cheese process, using 0.2 pm ceramic filters results in a fraction containing two major phospholipids, phosphatidylcholine and phosphatidylethanolamine, and lesser amounts of phosphatidylinositol, phosphatidylserine, sphingomyelin and cerebrosides (Boyd et al., 1999). The phospholipid fraction separated from the total lipids contains a larger proportion of mono- and polyunsaturated fatty acids (mainly oleic, Cig i and linoleic, C ) compared to the total lipid and the neutral lipid fraction (Boyd et al., 1999). 

There are two types of whey, classified (7) according to source (1) "sweet" whey, which is derived from the manufacture of products in which rennet-type enzymes are used to coagulate milk (e.g. Gouda and Cheddar cheeses), and which has a minimum pH of... 

Hayes et al. (21) studied the effects of pH variation on the ultrafiltration of Cheddar cheese and HCl casein wheys. Their earlier work had shown that both wheys gave low flux rates at pH... 

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 ... 

Table 3.7 Composition of Cheddar and Cottage Cheese Whey...

Approximately 90% of the citrate in milk is soluble and is lost in the whey however, the concentration of citrate in the aqueous phase of cheese is approximately three times that in whey (Fryer et al., 1970), reflecting the concentration of colloidal citrate. Cheddar cheese contains 0.2 to 0.5% (w/ w) citrate which decreases to 0.1% at 6 months (Fryer et al., 1970 Thomas, 1987). Inoculation of cheesemilk with Lb. plantarum accelerated the depletion of citrate pediococci did not appear to utilize citrate (Thomas, 1987). 

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