Cover

Traditional Cheesemaking (SKAT, 1989, 74 p.)[edit | edit source]

Part III: Beyond cheesemaking[edit | edit source]

Chapter 1: Other foods from milk[edit | edit source]

Whey

The whey removed from the cheese vat after the initial stirring of the curd and before the addition of hot water and salt is rich in fat and albumin, a milk protein which is not coagulated by rennet.

The appropriate composition of whey is:

water

93%

lactose

4.8%

protein (albumin)

0.7%

fat

0.8%

minerals

0.7%

The mineral salts and lactose, the major solid component creating the sweet flavour of the whey, are dissolved in the whey and can only be recovered by the concentration of the whey by evaporation to 60 per cent solids followed by cooling. The fat can be removed either with a mechanical decreamer, or by leaving the whey overnight until the cream rises to the surface. This cream makes a butter which is considered to have an inferior taste but which is excellent for baking. The albumin can be separated from acidified whey and used with or without fat to make Ricotta. After the fat and protein have been removed, the whey' which is rich in lactose and mineral salts, is usually fed to farm animals (Figure 16).

File:SK17056A.GIF
Figure 16. Transformation of whey and its by-products

Ricotta (whey cheese)

Fresh Ricotta has a bland flavour and is made from albumin, obtained by heating whole or separated acidified whey, to which milk may have been added.

Method

Preparing the bacterial culture

Incubate a few bottles of whey from the cheese vat at 38 C for 24 hours until it reaches an acid level of 200 Dornic. A small quantity of yoghurt starter culture may be added to stimulate acidification.

Heating the whey

Heat the whey to 80 to 85 C. It should not be acidified until it reaches the indicated temperature. Add about 10 per cent of the whey starter, or 250 g of granular citric acid dissolved in two litres of water for 500 litres of whey, or 0.4 per cent white vinegar. Stop the agitation after the addition. Continued heating carries the submerged curd particles to the surface, but the fire should be kept very low. Let the curd rest for 15 minutes. Floating is influenced by the amount of fat and acid. Adding some skimmed milk or buttermilk, when the whey reaches 85 C helps to trap fine particles of albumin more effectively by collecting them into larger units. Buttermilk gives the product a smoother and softer texture. If too much agitation is applied or there is excess acid, the curd mass will settle to the bottom of the vat and the separation from the whey will be very difficult.

Transfer the floating curd from the surface into a fine cheesecloth with a perforated scoop. If the precipitated albumin fails to rise to the surface, the whey may be strained through fine cheesecloth into another tank. Tie the four corners of the cheesecloth together and suspend it above the draining tank for four to six hours to drain.

It is difficult to believe that acid cheese, which has been sterilized at more than 80 C is so susceptible to microbial spoilage. Ricotta cannot be preserved for very long because of its high moisture content, and should be eaten fresh, either on its own, or with salt, spices, sugar cinnamon or with sweet fritters.

Conversion

One hundred litres of whole whey contains approximately 700 grams of albumin and 800 grams of fat a total of 1.5 kg of removable solids. This yields 3 kg of Ricotta, since Ricotta contains more than 50 per cent of water. Given this low yield, the cheapest form of fuel available should be used.

Cream

Cream, the concentrated fat from milk, is derived directly either from milk or from the whey.

The cream from milk differs in composition from the cream obtained from whey, and the composition can be measured with a butyrometer or simply by eye.

The composition of cream.


Whey cream

water

60.0%

58.0%

fat

35.0%

37.0%

lactose

2.5%

3.5%

protein

2.0%

1.0%

minerals

5%

0.5%

Milk fat has a relative density of 0.93, less than water (1,000 litres of milk weigh 1,031 kg, while 1,000 litres of cream weigh 930 kg); consequently, as cream is less dense than milk, the cream rises to the surface of the milk.

Separating, or skimming the milk or whey, is the first step in buttermaking and can be done in two ways: naturally or mechanically.

Natural separation

The milk is left to stand undisturbed overnight so that the cream rises to the surface and can be skimmed off with a spatula or flat spoon, agitating the milk as little as possible. This traditional way of removing cream, used by cheesemakers who have no machinery, has the disadvantage of leaving a relatively large amount (more than one per cent) of cream in the milk.

Mechanical separation

Milk passes through a high velocity centrifuge (Figure 17). This separates the milk from the cream and they each flow out of separate outlets. Mechanical separation is more expensive, but is more rapid alla efficient than natural decreaming. The cream is almost completely separated from the milk, which contains only 0.05 to 0.10 per cent fat. Large decreaming machines have a dial which controls the percentage of cream to be removed.

File:SK17058A.GIF
Figure 17. A mechanical cream separator

Pasteurization of cream

Fresh cream contains large numbers of bacteria which will damage butter and therefore should be pasteurized to eliminate all bacteria, both harmful and beneficial. As cream is more viscous than milk, it requires a slightly more severe pasteurization: it should be heated to 75 C for 10 to 20 minutes.

Butter

Whey cream butter, having passed through the long cheesemaking process, has a shorter shelf-life than milk cream butter. Special attention should, therefore, be paid to maintain the correct pasteurization temperatures.

Maturation

For cultured butter cool the cream to 25 C after pasteurization, a favourable temperature for the development of the bacteria in lactic starters. Add five per cent lactic culture, with flavour-producing bacteria, and leave the cream for 10 to 16 hours until it develops an acid taste. If left for too long, the cream will become so acidified that whey will begin to appear at the bottom of the tank; this is not desirable. As a general rule, the cream should not exceed 45 to 55 Dornic. Cool the cream to 12 C.

Churning

Churning throwing the cream against a surface transforms it into butter. The cream thickens and becomes spongy as the fat globules mass together, becoming solid grain-size pieces of butter which float to the surface of the cream whey, the whitish liquid called buttermilk. As soon as the cream thickens and before the grains of butter form a mass, the churning should stop. Either the whey should be drained off or the butter strained out with a sieve. If the grains of butter are allowed to stick together they will re-absorb droplets of whey, increasing the amount of lactose present and giving the butter a short shelf-life. Churning normally takes 20 to 40 minutes and a churning temperature of 12 to 14 C should be observed.

Washing

Washing the butter grains prolongs its shelf life by removing any residue whey. Excessive washing, however, can destroy its taste and aroma. The water spring-or rain-water is suitable must be clean and free from harmful bacteria, or the effects of pasteurization will be annulled. The water should also be cool between 10 and 12 C in fact, the cooler the better.

Washing three times is usually sufficient to remove the buttermilk residue: when the rinse water running off the butter is clear rather than cloudy, the butter is ready.

Salting

Salt is added to butter to improve its flavour and help to preserve it, as salt delays the growth of microbes. There are two methods for salting butter:

  • Dry salting - Here, two to three per cent of fine clean salt is added to the butter after washing and carefully mixed in to ensure uniformity.
  • Wet salting - This method is used when fine salt is not available.

Between two and three per cent of clean coarse salt is added to the final washing water. It must be well-dissolved and if not completely clean or dissolved the solution should be filtered several times before use. The butter should not be allowed to mass together before the salt solution is added or the butter will not be evenly salted.

Pressing

Pressing the butter, either manually or mechanically, removes any droplets of water that remain from washing in order to further its shelf life.

Butter churns usually have a pair of rollers which press the butter after washing is complete.

Moulding and packing

Butter is moulded into small blocks of one quarter or half a kilo with wooden forms and tops. These forms must be moist and cool so that the butter does not stick. After moulding the forms are often lined with wax paper that adheres to the butter when they are removed. The butter is packed in opaque cartons to ensure that light, which rapidly turns butter rancid, does not penetrate.

Composition

Good butter should have an adequate fat and a low moisture content less than 16 per cent. It should not contain much protein nor lactose as these components would feed unwanted bacteria. Unsalted butter must be especially well-treated in order to keep an agreeable taste and aroma.

Butter is composed of:

Fat

81%

Water

16%

Salt

2.5%

Protein

0.5%

Conversion tables for cream and butter.

Starting material

Converted material

Yield

Milk

Cream

10%

100 litres, 3.3% fat 1

10 litres,32% fat


Milk cream

Butter

40%

10 litres, 32% fat

4 kg, 80% fat


Milk

Butter

4%

100 litres

4 kg





Whey/Cream/Butter



Whey

Cream

2%

100 litres, 0.5 to 1% fat 2

1.5 to 3 litres, 33% fat





Whey cream

Butter

40%

1.5 to 3 litres

800 to 1,200 g


1. If milk is skimmed, 0.1% fat is lost.
2. Buttermilk (0.5 to 1 per cent fat) mixed with cheese whey and passed through a decreamer can yield more cream.

File:SK17061A.GIF
Figure 18. Making yoghurt


Chapter 2: The rural cheese factory[edit | edit source]

Location

The location of pasture grounds (so that the milk is not transported too far), climate (temperature and humidity), access to water and drainage are the most essential factors which must be considered when deciding where to build a cheese factory.

In tropical regions cheese factories are usually located at an altitude of 2,000 to 4,000 m, where temperatures are ideal for cheese ripening and buttermaking. Rapid temperature changes must be avoided and draughts must be excluded from the factory as much as possible.

As a cheese factory requires large quantities of cool, fresh, bacteriafree water (10 litres for every litre of milk processed 3,000 litres daily for 300 litres of milk), it should be built, ideally, near a spring or fresh mountain stream and the water piped directly into the plant.

The site should be built above, not below, a town and at least 100 m from byres, stables and pig-styes, to avoid contamination from sewers, refuse and animal dirt, and should be elevated to allow fast, easy drainage. People tending animals should not enter the cheese factory.

Construction

Floors

Concrete floors are preferable as they can be washed and drained daily and are strong enough to withstand blows from steel churns and tanks. They should be inclined for fast efficient drainage and must be smooth and unbroken: holes and cracks are difficult to clean and also trap dirt and micro-organisms.

Drainage

Waste water must be carried well away from the plant in closed pipes which are covered at each end with wire screen to exclude rodents and with U bends or other traps to prevent odours entering the factory.

Walls

Cement walls should be painted with lime to kill microbes and repainted every three months. A sandy plaster applied to a height of one metre allows the walls to be hosed down. If available, tiles make an excellent surface in the cheese room and plastic or rubberized paints are useful, if available.

Roof

Tile roofing is a good insulator, keeping out excessive heat or cold. If galvanized roofing is used, insulated ceilings must be installed as well, to prevent fluctuations of temperature. A small roofed lintel over the main door helps to prevent an accumulation of muck on the entrance floor. Beware: condensation on the underside of galvanized roofing falling into a vat could be dangerous.

Doors and windows

The main door should be wide enough to allow tanks and other large equipment to be brought in, and should open outwards to save valuable space. Windows should be installed at both ends of the plant for good ventilation and should be large enough to allow sufficient air and light to enter to control bacterial growth. Screens on doors and windows keep out insects.

Layout

The layout of the plant should allow for easy access to equipment, maximum convenience and good work-flow. Local engineers and metalworkers can often design and make equipment to a very high standard at a far lower price than imported goods, and should be used as much as possible. Four rooms the cheese room, maturing room, storeroom and office and an outside reception area are the factory's minimum requirement and each need different environmental conditions. They should all be on the same level (except in the case of a gravity circuit, see Figure 19), partly to simplify drainage and water disposal, but also because stairs are a great inconvenience (Figure 20).

File:SK17065A.GIF
Figure 19. Gravity circuit of a 2,000-litre cheese factory

File:SK17066A.GIF
Figure 20. Plan of a 600-litre-capacity cheese factory (1:75 scale)

Reception

As only cheesemakers and assistants should be allowed inside the plant, and to prevent dust and mud from entering, the reception area should be outside the plant, near the cheese room. A concrete platform with a tank and water-tap in the reception area permits easy washing of transport tanks and churns; make sure that water can run off, and not remain as puddles.

Cheese processig room

This should be quite a warm room containing the equipment for analysis, pasteurization, cheesemaking and pressing. The tanks should be near the pressing table.

Curing or ripening room

The curing and ripening process is as important as the cheesemaking process. Each type of cheese needs its own specific environment and this book has described Andino, Tilsit, Danbo and Gruyere which require a temperature of between 12 and 15 C and a humidity of 85 to 90 per cent. Very often (even in the most suitable geographical areas), these conditions do not occur naturally throughout the year and in designing cheese factories, it is essential to plan the ripening rooms in the best possible location.

Ripening rooms can be semi earth-sheltered, or installed in old adobe houses with very thick insulating walls. A false ceiling built under the roof insulates the room better. There should be few windows, none receiving a lot of light, and ideally, the room should be protected by trees. The windows can be opened at night, to allow a flow of air if the humidity is too high and strong window screens can be used to prevent insects and animals from entering.
If the humidity drops too low the floor of the ripening room can be flooded with a few centimetres of water to provide the necessary moisture.

Small factories (up to 600 litres of milk a day) need a maturing room of about 5.5 by 4 m. There should be long narrow shelves of three-quarter inch galvanized metal water-tubes, which do not rust. The end supports (see Figure 21) can be made of wood, into which horizontal tubes can be easily fitted. Boards to hold the cheeses should be short, light and easily moved, so that they can be taken out, washed, sterilized and replaced by clean dry boards weekly. Almost any kind of wood can be used to make these planks the less porous, the better except plywood. Certain very green woods secrete substances that can stain the cheeses. In these cases, first soak the boards in water for several hours and then dry them well.

The brine tank (see Figure 21) can also be located in the maturing room. The size depends on the number of cheeses, but should be about 80 cm high and made of cement. To facilitate working with the tank, fill the first 20 cm with concrete, the next 30 cm with the brine solution, and allow the top 30 cm for the increase in volume when the cheeses are added. Incline the bottom slightly towards an outlet that is opened to drain the tank about every two months. Tile the inside and the outside of the tank with durable white tiles which are both inexpensive and easy to clean. Because the high moisture and salinity content of the air in the maturing room is detrimental to metal and wood alike nothing else should be located there.

File:SK17067A.GIF
Figure 21. Basic equipment for the cheese factory

Equipment storage room

The equipment storage room, next door to the maturing room, is used to keep shipping boxes, salt, and various other necessary items. The doorway of the storage room leads to the outside, close to the drying and packing room.

In larger cheese factories (1,000 to 1,500 litres of milk per day) there should be:

· a curing room with brine tank and the fresh cheeses up to one week old;
· a ripening room for Andino, Tilsit, Danbo;
· a ripening room for Gruyere;
· a drying and packing room.

Drying and packing room

Just before the cheese is ready to be sold, it is washed with cold water and scrubbed with a soft brush. It is kept in the drying room for one to two days. When it is dry, it is covered with a liquid plastic (Foodplast or Mowilith) which is applied with a sponge. Foodplast or Mowilith are often used, but other forms of polyvinyl acetate are available and waxing or other forms of packaging can be used. The top half is sponged first, left to dry for half a day, then turned over for the bottom half to be sponged. The label is immediately placed on top of the liquid plastic so that it will dry and adhere to the cheese. The cheeses are then weighed and packed, ready to be sold.

Equipment for a 600-litre-capacity cheese factory

Cheese processing

  • Cheesemaking vat (stainless steel, double jacket, 600 litre capacity)
  • Kerosene burner
  • Cheesecutting harp or multi-bladed 'American knives'
  • Wooden paddle
  • Hanging scale
  • 4 plastic buckets
  • Brushes and brooms
  • Water filter
  • 5 40-litre cans (plastic or aluminium)
  • 1 clock
  • 1 plastic scoop
  • 2 thermometers
  • Plastic aprons
  • Plastic containers for whey, total capacity of 600 litres
  • Water hose for cleaning
  • Fine cloth to strain the milk (to stretch over the vat)

For moulding the cheese

  • Wooden table (see Figure 21). (Stainless steel is preferable, but costs about 15 times as much).
  • Moulds:

Tilsit cheese = 25 cylinders of 20 cm diameter and 15 cm height
Andino cheese = 70 cylinders of 15 cm diameter and 25 cm height
Fresh (white) cheese = 85 cylinders of 10 cm diameter and 25 cm height (each mould = 2 cheeses)
Danbo cheese = 13 rectangular pieces of 25 x 25 x 15 cm height (made of wood)

Note: since these moulds are not found on the market we have made our moulds from pieces of drainage pipe made of strong plastic. We cut pieces from the drainage pipe to the measurements indicated, and drill holes of 3 mm in diameter at distances of 2 cm.

  • 25 wooden discs of 20 cm diameter (to fit inside the moulds)

70 wooden discs of 15 cm diameter
13 wooden covers of 25 x 25 cm

(Note: fresh, white, South American cheese does not need discs)

  • 25 weights of 6 to 8 kg measuring 20 cm in diameter 70 weights of 4 kg measuring 15 cm in diameter 13 weights of 10 kg each (24 x 24 cm) to fit inside the moulds
  • 2 stainless steel trays with 42 holes each; these are placed over the 42 white cheese moulds, in order to fill them quickly.
  • 3 m of thick nylon mesh (2 mm squares) to place under the moulds.
  • 20 m of fine cheesecloth for cutting and rolling each cheese separately.
  • 5 m of plastic to cover the cheese in the moulds.

Laboratory

  • table (wooden or built-in)
  • gas stove with two burners
  • wooden incubator to prepare cultures
  • three pots (aluminium) to prepare cultures (15 litres, 10 litres, 5 litres)
  • six plastic containers of one or two litres each, with large neck and lid
  • two big knives to cut cheese
  • milk testing:
  • Cheese wire-cutters.

Ripening room

Shelves: see Figure 21 100 planks of 80 x 25 cm strong table for curing the cheeses plastic containers for delivering the cheeses

Daily necessities

Rennet, freeze-dried cultures, calcium chloride, salt, detergent, kerosene, gas, plastic bags for fresh (white) cheeses, labels for ripened cheeses, paper for wrapping ripened cheeses, foodplast, brushes, reagents for testing.

Production costs

Unstable exchange rates and unpredictable currency fluctuations make it impossible to provide a set of figures which all readers of this book will find realistic. The following figures, therefore, which are based on production costs in Ecuador in August 1986, are intended to serve only as a guide to the approximate relative outlays required for equipment, materials, and labour.

Soft South American white cheese

Sucres Ecuatorianos (1

200 litres of milk (18.00 Sucres each)

3,600

5 g of rennet powder

76

20 g of calcium chloride

20

cultures (2 freeze-dried bags every month)

20

3 kg of salt

120

57 plastic bags

102

1 bag of detergent

25

9 litres of kerosene

18

gas

19

labour costs

200

transportation of the cheese to market

31

expenses for the accompanying person

27

depreciation

78

interest (12% per year)

133

other

99

PRODUCTION COSTS

4,568

sale of 57 cheeses at 95 Sucres each2

5,425

Profit

856

Andean Cheese

Sucres Ecuatorianos

200 litres of milk (18.00 Sucres)

3,600

5 g of rennet powder

76

10 g of calcium chloride

20

2 freeze-dried cultures every month

20

3 kg of salt

120

24 labels

41

detergent

25

9 litres of kerosene

18

gas

19

labour

200

transportation of the cheese to Quito

100

accompanying personne

127

depreciation

78

interest (12% per year)

133

other

99

PRODUCTION COSTS

4,506

sale of 23.5 Andino cheeses (250 Sucres each) 1

5,876

Profit each day

1,365

1 8.5 litres of milk = 1 Andino cheese of one kg. The cheese is sold within 10 to 15 days and keeps for several weeks at a temperature of about 15 C.

Key points for successful rural cheesemaking

Milk Production

  • Milk production from the same cows can be increased considerably if the quality and quantity of the feed is high. This can be done by a reasonable use of pasture, including field rotation and even distribution of natural soil fertilizer. It is important to keep individual cow yields and to breed from the best. Pedigree cows only should be bought when adequate handling and balanced feed is assured.
  • Cheesemakers should visit milking stations to encourage care in cleanliness and to test for mastitis. They also need to inform the farmers of the dangers of selling milk that has come from cows which received antibiotics less than five days earlier.
  • Mastitis is controlled basically with careful handling of the cows and hygienic milking. Only in cases of clinical mastitis are antibiotics recommended.
  • The government must be encouraged to sponsor health programmes for cattle and co-operate with vaccination programmes to eradicate bovine brucellosis.

HEALTHY COWS, CLEAN MILKING AND RAPID MILK TRANSPORTATION TO THE CHEESE FACTORY IS THE FORMULA FOR SUCCESS.

From milk to cheese

  • Cheesemakers must analyse the milk upon reception in the cheese plant: smelling, checking colour and hygiene. Density tests must be made twice weekly and reductase tests once a week. The results should be noted regularly and discussed with farmers.
  • The technical process should be recorded daily, so that it can be compared with the final quality of the cheese and eventual problems can be pinpointed.
  • All the equipment as well as the factory itself must be cleaned at the end of each process.
  • Each day the cheesemakers must have enough hot water available so that transporters bringing the milk can immediately wash their containers. All milk buckets have to be checked regularly by the cheesemakers.
  • Cheesemakers must work carefully, so as not to break any utensils, waste milk or curds or use more rennet than is needed to coagulate the milk in 30 to 35 minutes.

Administration

  • The administration must co-ordinate daily activities and responsibilities for each cheesemaker. Since experience only comes after at least three years of work, it is better not to change cheesemakers often.
  • Bookkeeping must be done daily, as well as keeping records of daily production yields. An inventory of materials and an economic balance must be made every three months.
  • Cheesemakers must be paid an appropriate wage, as well as a production incentive bonus.
  • Farmers should be rewarded for excellent milk quality. The result of the processed products depends not only on the experience of the cheesemaking personnel but also on the quality of the milk.

PERSONAL HYGIENE, CLEAN EQUIPMENT AND ORDER IN THE FACTORY ARE INDISPENSABLE FOR HIGH QUALITY PRODUCTS.