Cheese manufacturing

Enzymes are used in baking, cheese manufacture, wine-making, brewing and distillation, pharmaceuticals, leather tanning, paper manufacture, adhesives, sewage disposal, animal feeds and in detergents. 

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). 

Soybean-Based Cheese. In tofu cheese manufacture, the soybeans are cooked to give soy milk, then formed into a curd using calcium sulfate, and pressed to give tofu. The tofu is inoculated y ctinomucor elegans fermented, salted, and aged to form sufu (soft cheese) (17). This product is widely used ia the Orient and is gaining acceptance ia the United States. 

Lactose, the milk sugar, is a reducing disaccharide consisting of glucose and galactose moieties. The estimated annual worldwide availability of lactose as a byproduct from cheese manufacture is several million tons [1,2], but only about 400 000 t/a lactose is processed further from cheese whey [3], Non-processed whey is an environmental problem due to its high biochemical and chemical oxygen demand [2], The use of lactose as such is limited by two main factors relatively low solubility of lactose in most solvents and lactose intolerance in human body [1]. 

Cheese manufacture/production, 10 296 recombinant yeast in, 26 492 salt in, 22 815... 

Ripened cheeses contain higher average concentrations of amines than do unripened cheeses, a difference that could be related to processing (Martelli et ah, 1993 Schneller et al., 1997). Casein proteolysis that occurs during cheese manufacture may result in an increased level of free amino acids. These amino acids are then decarboxylated, resulting in the formation of biogenic amines. A... 

Fernandez-Garcia E., Tomillo, J. and Nunez, M. (2000). Formation of biogenic amines in raw milk Hispanico cheese manufactured with proteinases and different levels of starter culture, J. Food Prot., 63, 1551. 

The Daily Industiy. The first step in cheese manufacture is the coagulation of milk. Coagulation can be divided into two distinct phases, enzymatic and the non-enzymatic. In the primary enzymatic phase a proteol ic enzyme such as chymosin (rennet), or less effectively, pepsin, carries out an extremely specific and limited proteolysis, cleaving a phenylalanine-methionine bond of /c-casein, making the casein micelle metastabie. In the second, non-enzymatic phase, the... 

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. 

Rhizomucor miehei secretes a lipase that is reported to give satisfactory results in Italian cheese manufacture. This enzyme has been characterized and is commercially available as Piccantase . Lipases secreted by selected strains of Penicillium roqueforti and P. candidum are considered to be potentially useful for the manufacture of Italian and other cheese varieties. 

Figure 10.11 pH profile of Cheddar during cheese manufacture. 

Acid production plays several major roles in cheese manufacture ... 

Minerals found in milk which are insoluble remain in water in the curd and are more concentrated in the cheese than in milk. About two-thirds of the calcium and one-half of the phosphorus of milk remains in cheese. A major portion of the milk calcium is retained in the curd of cheese made with coagulating enzymes. Acid coagulation alone results in the loss of portions of both calcium and phosphorus salts in the acid whey, since these minerals are more soluble in the acidic medium. Most milk fat and fat-soluble vitamins are retained in the curd, but a considerable amount of water-soluble vitamins is lost during cheese manufacture. Retention of part of some B-complex vitamins in curd is due to their extended association with casein in the original milk. 

Tambat R.V. and Srinivasan, M. R. 1979. Changes in surface tension, viscosity and curd tension of buffalo and cow milk during Cheddar cheese manufacture. Ind J. Dairy Sci. 32, 173-176. 

Recent reviews (Green 1977 Phelan 1977 Visser 1981) have dealt with the role of milk-clotting enzymes in cheese manufacture, while Foltmann (1981) has provided an excellent discussion of the structure of chymosin and its enzymic properties. 

Fungal proteases have been investigated extensively in search of suitable milk clotting enzymes. Patents have been issued for production of rennets from E. parasitica, M. Pusillus var. Lindt and M. miehei var. Cooney et Emerson. These have been approved in the United States as secondary direct food additives (FDA. 1984B) and have experienced considerable commercial success in the United States as milk-clotting enzymes for cheese manufacture. Many other fungal sources have also been tried in the effort to find an inexpensive replacement for chymosin. 

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. 

Babel, F. J. and Somkuti, G. A. 1968. Mucor pusillus protease as a milk coagulant for cheese manufacture. J. Dairy Sci. 51, 937-937. 

Dimitroff, D. and Prodanski, P. 1973. Use of enzyme preparations of microbial origin in kachkaval cheese manufacture. Production of ewes and cows milk kachkaval cheese using an enzyme preparation from Bacillus mesentericus. Milchwissen-schaft 28, 568-571. 

Richardson, G. H., Nelson, J. H., Lubnow, R. E. and Schwarberg, R. L. 1967. Rennin-like enzyme from Mucor pusillus for cheese manufacture. J. Dairy Sci. 50, 1066-1072... 

Richardson, G. H., Okigbo, L. M. and Thorpe, J. D. 1983. Continuous measurement of curd tension during cheese manufacture. Proc. 6th Int. Congr. Food Sci. Technol. 2, 148. 

Wang, J. T. 1969. Survival and distribution of rennin during Cheddar cheese manufacture. M.S. Thesis. Utah State University, Logan. 

Lawrence et al. (1984) suggested that all types of cheese can be best classified by their calcium content and pH. According to this classification scheme, the extent of acid production at various stages of cheese manufacture ultimately influences the body and texture of cheese. Cheeses can, therefore, be classified by manufacturing procedure rather than by flavor. 

Most varieties of cheese are cooked by applying heat to the outside of the vessel containing the curd and whey slurry. Gouda cheese curd is heated by first draining a portion of the whey and then adding hot water. The proportion of whey removed and water added is varied to control the amount of residual lactose in the curd. Washing of the curd is also used in cottage and brick cheese manufacture to remove lactic acid and lactose, but in these cases the cheese curds have first been heated. 

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