Section A: Getting Started

Introduction to Cheese Making

The Basic Process

Cheese making can be described as the process of removing water, lactose and some minerals from milk to produce a concentrate of milk fat and protein. The essential ingredients of cheese are milk, coagulating enzyme (rennet), bacterial cultures and salt. Rennet causes the milk proteins to aggregate and ultimately transform fluid milk to a semi-firm gel. When this gel is cut into small pieces (curds), the whey (mostly water and lactose) begins to separate from the curds. Acid production by bacterial cultures is essential to aid expulsion of whey from the curd and largely determines the final cheese moisture, flavour and texture. A flow chart showing the general operations of cheese making is in Figure 1.1.

Figure 1.1 Flowchart of Cheese Making Process.

Cheese Families

The objectives of cheese making are: (1) To obtain the optimum cheese composition with respect to moisture, acidity (pH), fat, protein and minerals (especially calcium); (2) Establish the correct structure of the cheese at the microscopic level; and (3) Ripen to perfection. Objectives (1) and (2) are achieved by varying initial make procedures and it is then possible to achieve objective (3). Most of these variations in initial make procedures are different means to control the rate and extent of acid development, and the rate and extent of moisture release. Grouped according to texture and basic manufacturing procedures, seven cheese families are described below and summarized in Table 1.1. Table 1.2 contains composition data for some common cheese varieties.

 

Table 1.1: Some properties of cheese categorized according to type of coagulation and procedures used for pH and moisture control. Adapted from Hill (2007). Plus signs in column three indicate relative amounts.

 

Varieties

Coagulation

Moisture in non-fat-substance

pH at 4 – 7 days

Ca mM/Kg SNF

Curing Time

 

Acid Coagulated

 

Cottage, quark, cream cheese

 

Acid coagulation at pH 4.6-4.8

 

72-80%, aw 0.980 - 0.995

Controlled by cooking and washing treatments

 

4.3-4.8  

Inhibition of culture by low pH, high temperature cooking or cooling, and/or washing

 

50-350

 

Consumed fresh, short shelf life

Heat-acid Coagulated

Indian Paneer and Channa, Ricotta, Requeson. Useful as cooking cheese

Heat denatured whey proteins are co-precipitated with caseins by acid. Whey proteins inhibit melting

75-84%  Increases with whey protein content, decreases with cooking after acidification

5.0-5.8; Amount of acidulant added. 3-6% lactose in cheese due to absence of fermentation

 

Normally consumed fresh, limited shelf life unless hot packed, pickled, or packed in sugar syrup

Unripened: rennet coagulated

Some Latin American, middle eastern and European varieties. Useful as cooking cheese

Rennet++, Little or no culture, cutting near endogenous pH

60-80% Controlled by cooking, stirring out and draining conditions. Syneresis often occurs in the package

5.8-6.6; Little or no culture. High pH prevents melting

 

Consumed fresh. High pH limits shelf life

Soft Ripened:  High Acid

Feta, Camembert, Blue

Rennet+++, culture+++; ripening time+++, cutting at pH < 6.5

60-70%, aw 0.96-0.99

Syneresis induced by acid development and by salting

4.5-4.8. Controlled by acid inhibition of culture, salting and cooling.

400-600

2-8 weeks

Semi-hard Cheese:  Washed

Gouda, Edam, Colby, Havarti, Montasio and many others

Rennet++, culture-+, ripening time++, Cutting at pH < 6.6

55-65%, aw 0.95-0.97

Controlled by cooking, temperature of wash water, rate of acid development, curd handling, salting treatments

5.0-5.2 Controlled by washing to remove lactose and other treatments such cooking, culture selection and salting.

500-700

2 weeks-9 months

Hard Cheese:  Low Temperature

Cheddar, Provolone

Rennet++, culture++, ripening time++, cutting at pH < 6.6

52-60%, aw 0.94-0.96

Controlled by cooking, curd handling, rate of acid development and salting

Rate of acid development and moisture control determines residual lactose; draining pH is critical

500-700

1-24+ months

Hard Cheese:  High Temperature

Swiss types, Italian types such as parmesan

Rennet+, culture+, ripening+ (little or none for Swiss), cutting at pH near 6.6

39-52%

Controlled mainly by high temperature cooking (52-55ºC)

Acidity and moisture determine residual lactose; draining pH is critical

600-800

1-24+ months

 
Table 1.2: Typical composition (% by weight) of some cheese varieties.  Adapted from Hill (2007).

Type

Cheese

Moisture

Protein

Fat

Total

CHO

FDM

Ash

Ca

P

Salt

Retail pH

Acid Coagulated

Cottage

Creamed cottage

Quark

Cream

Neufchatel

79.8

79.0

72.0

53.7

62.2

17.3

12.5

18.0

7.5

10.0

0.42

4.5

8.0

34.9

23.4

1.8

2.7

3.0

2.7

2.9

2.1

21.4

28.5

75.4

62.0

0.7

1.4

 

1.2

1.5

0.03

0.06

0.30

0.08

0.07

0.10

0.13

0.35

0.10

0.13

nil

1.0

 

0.73

0.75

5.0

5.0

4.5

4.6

4.6

Heat-Acid Coagulated

Chhana

Frying cheese

Ricotta-3% fat milk

Ricotone-from whey & milk

53.0

55.0

72.2

 

82.5

17.0

19.7

11.2

 

11.3

25.0

20.4

12.7

 

0.5

2.0

3.0

3.0

 

1.5

53.2

44.8

45.7

 

2.9

 

 

 

 

3.0

<0.5

 

<0.5

 

5.4

5.9

 

5.8

Fresh Rennet Coagulated

Queso Blanco

Queso de Freir

Italian fresh cheese

52.0

52.4

49.0

23.0

23.0

28.0

20.0

19.5

16.0

 

 

42.0

41.0

31.4

 

 

 

2.5

3.0

nil

5.8

5.8

6.5

Soft Ripened

Camembert

Feta

Blue

Gorgonzola

51.8

55.2

42.0

36.0

19.8

14.2

21.0

26.0

24.3

21.3

29.0

32.0

0.5

 

2.3

 

50.3

47.5

50.0

50.0

3.7

5.2

5.1

5.0

0.39

0.49

0.53

 

0.35

0.34

0.39

 

2.1

 

3.5

 

6.9

4.4

6.5

 

Semi-hard Washed

Colby

Gouda

Edam

Fontina

Havarti-Danish

Munster

40.0

41.5

41.4

42.8

43.5

41.8

25.0

25.0

25.0

24.2

24.7

23.4

31.0

27.4

27.8

25.5

26.5

30.0

2.0

2.2

1.4

 

 

1.1

51.7

46.9

47.6

44.6

46.9

51.6

3.4

3.9

4.2

3.3

2.8

3.7

0.68

0.70

0.73

 

 

0.72

0.46

0.55

0.54

 

 

0.47

0.65

0.82

0.96

1.2

2.2

1.8

5.3

5.8

5.7

5.6

5.9

6.2

Hard Cheese Low-Temp.

Cheddar

Manchego-Spain

Provolone

Mozzarella

36.7

37.9

40.9

54.1

24.9

28.1

25.6

19.4

33.1

26.9

26.6

21.6

1.3

 

2.1

2.2

52.4

45.2

45.1

47.1

3.9

3.6

4.7

2.6

0.72

 

0.76

0.52

0.51

 

0.50

0.37

1.8

1.5

2.2

1.0

5.5

5.8

5.4

5.3

Hard Cheese High-Temp.

Parmesan

Romano

Swiss

Keflatyri-Greece

29.2

30.9

37.2

34.2

35.7

31.8

28.4

24.8

25.8

26.9

27.4

28.3

3.2

3.6

3.4

 

36.5

39.0

43.7

 

6.0

6.7

3.5

4.7

1.18

1.06

0.96

 

0.69

0.76

0.60

 

3.0

3.0

1.2

 

5.4

5.4

5.6

5.2

 

Family 1. Acid-coagulated Fresh Cheese

In North America, 'fresh cheese' normally refers to cheese produced by acid coagulation at 30 - 32°C with little or no added rennet. Acid is normally produced via fermentation by lactic cultures but some fresh cheese may also be produced by direct acidification with glucono-delta-lactone. Cheese made for fresh consumption is also made via rennet coagulation (Family 2) and a procedure known as heat-acid precipitation (Family 3).

Varieties: Cottage, Quark and Cream

Coagulation: The distinguishing characteristic of these varieties is that coagulation is achieved by acidification to pH 4.6 - 4.8, with little or no coagulating enzyme. Acidification is normally by lactic acid producing cultures. Most other American and European cheese varieties also use lactic acid producing cultures, but gelation is induced by a coagulating enzyme at pH 6.5 - 6.7, before much acid development has taken place.

pH Control: After cutting at pH 4.6 - 4.8, the curd is cooked to 52°C which is sufficient to inactivate the culture and prevent further acid development. Acidity is also reduced by washing the curd before salting.

Moisture Control: Curd moisture is reduced by syneresis during cooking but remains high, 60 - 70%, in the finished cheese.

Curing: Fresh cheese as the name implies is consumed fresh and has a shelf life of only 2 - 3 weeks.

Family 2. Rennet-coagulated Fresh Cheese

In Latin American, Middle Eastern and some European countries, fresh rennet cheese is produced with little or no culture. Without acid production by lactic acid bacteria, cheese pH remains high and the resulting cheese does not melt when used in a stir fry or other cooked recipes. For reasons of safety and quality, these varieties must be handled with extra attention to sanitation and refrigeration.

Varieties: Queso Blanco, Queso Fresco, Italian fresh cheese, Halloumi

Coagulation: The distinguishing characteristic of rennet coagulated fresh cheese is that little or no culture is used. Coagulation is, therefore, entirely by rennet at the natural pH of milk.

pH Control: The pH is determined by the amount of culture. If no culture is used, the pH remains in the range of 6.5-6.7. In some Queso Blanco varieties a small amount of culture is used to reduce the pH to about 5.8 which reduces the growth of both spoilage (increases shelf life) and pathogenic (increases food safety) microorganisms. Further acidification is inhibited by cooling and salting. Too much acidification below pH<5.8 will produce a meltable cheese which is unsuitable for frying.

Moisture Control: Curd moisture may be reduced by syneresis during cooking and limited acidification, but is still 50 - 70% in the finished cheese. Some varieties exhibit syneresis after packaging.

Curing: Consumed fresh and has a shelf life of only 2 - 4 weeks.

Family 3. Heat-Acid Precipitated Cheese

All cheese making involves a coagulum of milk proteins which is normally formed in one of three ways.

  1. Enzymatic coagulation of the primary milk protein, casein, where the enzyme, rennet, is the primary coagulating agent. Acid production by lactic cultures encourages coagulation and has important effects on the final cheese texture, but the primary coagulating agent is rennet. This is true for Cheese Families 2, and 4 - 7.
  2. The second type of coagulation is acid induced coagulation of casein, as in Cheese Family 1, where the acid is produced by natural fermentation or sometimes by the slow release acidulating agent, glucono-delta-lactone. All the cheese in Family 1, are acid coagulated in the temperature range of 20 - 35°C. In this temperature range, a pH of less than 4.9 is required to form the coagulum, although some fresh cheese is fermented to pH as low as 4.4.
  3. The third type of coagulation, like the second, is primarily acid induced, but no fermentation is involved and the acid is added to hot milk at temperatures in the range of 75 - 100°C. This process has the unique properties that: (i) The heat treatment denatures the whey proteins which can then be coagulated along with the casein and recovered in the cheese, hence, a huge yield advantage; (ii) The recovered whey proteins have a great capacity to bind water so that a high moisture but firm cheese can be produced, hence, another huge yield advantage; (iii) Acid coagulation at high temperatures requires less acidification, so the final cheese is much less acid with pH in the range of 5.2 to 6.0 rather than the range 4.4 - 4.8 required for the Family 1 varieties.
  4. Finally, the inclusion of whey proteins prevents cheese melting so this process can be used to produce frying/cooking cheese such as ricotta and Paneer.

Varieties: Ricotta (Italy), Channa and Paneer (India), some varieties of Latin American white cheese.

Coagulation: Coagulation is accomplished by direct acidification of heated milk. High heat treatment of milk (temperatures greater than 75°C) causes denaturation of the whey proteins. Subsequent acidification of the hot milk coagulates both casein and whey proteins, so that most of the milk protein is recovered in the cheese.

pH Control: The final acidity (pH) is determined by the amount of acid added. Final pH is normally in the range of 5.3 - 5.8. Any organic acid can be used, but lactic and citric acids are most common.

Moisture control: Moisture can be reduced by holding the curd in the hot curd-whey mixture after coagulation, and by draining and pressing procedures. Moisture is generally high (55 - 80%) due to the high water holding capacity of whey proteins.

Curing: Heat-acid precipitated varieties are normally consumed fresh. An exception is Mizithra, a type of ricotta cheese which is cured, dried, and consumed as a grating cheese. It is also possible in some cases to hot pack heat-acid varieties to obtain extended shelf life. High concentrations of whey proteins decrease cheese meltability and account for the excellent cooking properties of heat-acid precipitated cheese.

Family 4. Soft-Ripened Cheese

Varieties: Feta, Camembert, Brie, Blue

Coagulation: Coagulation is primarily rennet (enzymatic) with three important differences relative to cooked and pressed varieties (Families 5-7).

  1. The amount of lactic acid bacteria inoculum is large and the ripening period before renneting is extended. The result is that acidification has considerable influence on the development of curd structure during setting and demineralization of the curd is decreased.
  2. Cutting is delayed (i.e., setting time increased) to further encourage acidification and demineralization before cutting.
  3. Cutting is accomplished with large knives or just broken up with paddles to minimize moisture and fines losses before filling the forms.

pH Control: The distinguishing feature of these cheese is that the curd is placed in the forms while still sweet and let stand in a warm room for several hours. Acidification (i.e. conversion of lactose to lactic acid) continues until the accumulation of lactic acid inhibits culture growth. Acid development is also influenced by the time and amount of salting. The pH is normally about 4.4 - 4.6 on the day following manufacture and in the case of Feta remains low during curing, The pH of mould ripened varieties increases during curing (i.e., acidity decreases), especially Camembert and traditional Brie.

Note that most current versions of Brie use mild acid producing culture system to produce a sweeter Brie (lowest pH during early ripening is 5.0 - 5.2). This product ripens more slowly than conventional Brie and has a much greater shelf. 

Moisture Control: Syneresis is induced by acid development after forming and by brine salting. Moisture content is typically 45 - 60%.

Curing Time: 2 - 8 weeks.

Family 5. Semi-hard Washed Cheese

Varieties: This is the largest and most diverse group of cheese including Gouda, Edam, Colby, Brick, Montasio, Oka, Muenster and many others.

pH Control: The distinguishing feature of these cheese is the practice of washing to remove lactose. Part or all of the whey is removed and replaced with water to leach lactose from the curd. The objective is to limit the amount of lactose to a level which permits sufficient lactic acid development to produce a minimum pH of 5.0 - 5.2, but not enough to ferment and produce cheese pH less than 5.0.

Moisture Control: The amount of syneresis is controlled mainly by the temperature and time of cooking and by the temperature of the wash water. Higher temperatures during cooking or washing cause the curd to contract and expel moisture. Also, important are the rate of acid development and salting treatments. Washed curd cheese typically have moisture contents of 40 - 50%. With some exceptions, washing treatments are used to make cheese with a moisture content of 40% or greater and pH greater than 5.1. 

Curing: 2 weeks - 9 months. 

Family 6. Hard Cheese: Low temperature

Hard cheese (Families 6 and 7) are characterized by lower moisture (some pasta filata types excepted) than other families. Lower moisture permits removal of sufficient lactose by syneresis to avoid the necessity of washing. Low moisture is achieved by high temperature cooking (Family 7) or by controlled fermentation and curd handling (Family 6).

Varieties: Cheddar types and Pasta Filata. types. Cheddar and Pasta Filata manufacture are similar in the early stages. Pasta filata varieties are distinct in that they are worked and stretched in hot water and brine salted. Cheddar types are salted before hooping and pressing.

pH Control: The distinguishing feature of these cheese is that acid development is mainly controlled by the amount of syneresis. As with semi-hard cheese, the objective is to obtain a minimum pH of 5.0 - 5.2 within 1 - 3 days after manufacture. Lactose content is substantially reduced by fermentation with associated moisture loss during cheddaring and vat salting.

Moisture Control: Moisture is controlled by cooking temperature and time, stirring out after draining, cheddaring, amount of culture, and salting treatments. Typical moisture content is 35 - 39% for Cheddar types and up to 52% for Pasta Filata types.

Curing: 1 - 36 months.

Family 7. Hard Cheese: High Temperature

Varieties: Romano, Parmesan, Swiss

pH Control: Type of culture, time-temperature profile during pressing until cooling, lactose removed by syneresis. Little acid development before draining.

Moisture Control: Rapid syneresis induced by high renneting temperature and high cooking temperature.

Curing: 1 - 36 months.

Other Technological Criteria

The cheese families described above provide a useful 'coat rack' to help organize cheese according to the initial manufacturing procedures which determine cheese composition and its primary micro-structure. The following is a more comprehensive summary of technological parameters which determine cheese characteristics.

  • Species: cow, goat, sheep, buffalo, yak, other
  • Milk standardization
    • Fat and protein contents
    • Whey and milk blends
  • Coagulation
    • rennet gel
    • acid gel
    • heat-acid precipitate
  • Moisture control
    • Cooking temperature and time
    • Mesophilic versus thermophilic cultures
    • Amount and acidifying properties of the culture
    • Heat treatment of the milk
  • Type of pH control
    • Direct acidification vs fermentation
    • Amount and type of culture
    • Lactose removal:
      • Washing (American, Dutch)
      • High temperature syneresis (Swiss, Hard Italian)
      • High acid syneresis (Feta, Cheshire)
      • Cheddaring (Cheddar, Pasta Filata)
  • Extent of acid development
    • Low acid (minimum pH > 5.8), Latin American fresh cheese
    • Medium acid (minimum pH 4.9 - 5.5), most European varieties
    • High acid (minimum pH < 4.9), Fresh cheese, soft ripened cheese
  • Salting procedures
    • Salt before forming
    • Surface salt after forming
    • Immersion in salt brine
  • Type and duration of ripening
    • Fresh versus ripened
    • Interior, including blue veined cheese
    • Interior and surface ripened
      • Bacterial/yeast smears
      • White surface mould
  • Type of rind
    • Rindless-waxed, film wrapped, painted
    • Dry rind (cured at 85% relative humidity)
    • Surface ripened (cured at 90-95% relative humidity)
  • Texture
    • Openings: mechanical, small holes, large holes
    • Firmness
  • Melting properties
    • No melt: softening without flow (frying cheese)
    • Stretching: Low melt and strongly elastic (Mozzarella)
    • Fondue: Medium melt, medium elasticity (Raclette)
    • High melt: flows readily with no stretch (aged Cheddar)

 

Recommended references

See also References in the Dairy Science and Technology Education website.

Alfa-Laval. Dairy Handbook. Alfa-Laval, Food Engineering AB. P.O. Box 65, S-221 00 Lund, Sweden. [Well illustrated text. Excellent introduction to dairy technology].

American Public Health Association, Standard Methods for the examination of dairy products. 1015 Eighteenth St. NW, Washington, D.C.

Battistotti, B., Bottazzi, V., Piccinardi, A. and Volpato, G. 1983. Cheese: A guide to the world of cheese and Cheese making. Facts on File Publications, New York, NY.

Berger, W., Klostermeyer, H., Merkenich, K. and Uhlmann, G. 1989. Processed Cheese Manufacture, A JOHA guide. BK Ladenburg, Ladenburg.

Carroll, R. and Carroll, R. 1982. Cheese making made easy. Storey Communications Inc., Ponnal, Vermont. [Well illustrated manual for small and home cheese making operations]

Chandan, R. 1997. Dairy Based Ingredients. Amer. Assoc. Cereal Chemists, St. Paul, Minnesota.

Davis, J.G. 1965. Cheese. American Elsevier Publ. Co., New York.

Eck, A. and Gillis, J.-C., 2000. Cheesemaking from Science to Quality Assurance, Lavoisier Publishing, Paris..

Emmons, D.B., Ernstrom, C.A., Lacroix, C. and Verret, P. 1990. Predictive formulas for yield of cheese from composition of milk: a review. J. Dairy Sci. 73: 1365-1394.

Fox, P.F., Guinee, T.P., Cogan, T.M., McSweeney, P.L.H. 2000. Fundamentals of Cheese Science. Aspen Publishers, Inc. Gaithersburg, Maryland.

Hill, A.R. 1995. Chemical species in cheese and their origin in milk components. In Chemistry of Structure Function Relationships in Cheese, E.L. Malin and M.H. Tunick, Editors. Plenum Press, NY.

International Dairy Federation Special Issue No 9301. Factors Affecting Yield of Cheese.

Irvine, D.M. 1982. Cheddar Cheese Manufacture. A bulletin produced by the Ontario Ministry of Agriculture and Food. [Out of print]

Irvine, D.M. and Hill, A.R. 1985. "Cheese". In Comprehensive Biotechnology. M. Moo-Young, Editor.

Kosikowski, F.V. and Mistry, V.V. 1997. Cheese and Fermented Milk Foods, 3rd Edition, F.V. Kosikowski and Associates, Brooktondale, NY.

La Fondation de Technologie Laitiere et Department de Science et Technologie des Aliments Universite Laval. 1985. Dairy Science and Technology: Principles and Applications. Les Presses de l'Universite Laval, Quebec.

Law, B. 1999. Technology of cheese making Sheffield Academic Press, Sheffield, UK.

Lawrence, R.C., Heap, H.A. and Gilles, J. 1984. A controlled approach to cheese technology. J. Dairy Sci. 67: 1632-1645.

Leliévre, J., Freese, O.J. and Gilles, J. 1983. Prediction of Cheddar cheese yield. N.Z.J. Dairy Sci. Technol. 18: 169-172.

Masui, K.. and Yamada, T. 1966. French Cheeses: The Visual Guide to More than 350 Cheeses From Every Region of France. DK Publishing, New York.

Official Methods of Analysis of the Association of Official Agricultural Chemists, P.O. Box 540, Benjamin Franklin Station, Washington, D.C.

Pfizer Cheese Monographs. C. Pfizer and Co., New York.

  1. Italian Cheese Varieties
  2. American Cheese Varieties
  3. Cottage Cheese and Other Cultured Milk Products
  4. Ripened Semi-soft Cheeses
  5. Swiss Cheese Varieties
  6. Lactic Starter Culture Technology

Price, W.V. and Bush, M.G. 1974. The process cheese industry in the United States: A review. I. Industrial growth and problems. J. Milk and Food Technology 37: 135-152. II. Research and Development. Ibid 37: 179-198.

Robinson, R.K., Editor. 1990. Dairy Microbiology, Volumes 1 and 2. Elsevier Applied Science, NY.

Scott, R., Robinson, R.K. and Wilbey, R.A. 1998. Cheese making Practice. 3rd Edition. Applied Science. Publ. Ltd., London.

Troller, J.A. 1993. Sanitation in Food Processing. 2nd Edition. Academic Press. New York.

Walstra, P., Geurts, T.J., Noomen, A., Jellema, A. and van Boekel, M.A.. 1998. Dairy Technology. Marcel Dekker Inc. New York, NY.

Wong, N.P., Jenness, R., Keeney, M. and Marth, E.H. 1988. Fundamentals of Dairy Chemistry. Van Nostrand Reinhold Company, New York, NY.

Websites

Dairy Science and Technology Education website at the University of Guelph

Centre For Dairy Research, Madison, WI. http://www.cdr.wisc.edu/

Agriculture Canada, http://res2.agr.ca/

Others: 

http://www.cheese.com/