The composition of milk

Milk is a delicately balanced natural product. This rich, nutritious substance is composed mainly of water, lactose, fat, protein, mineral salts and various micro-organisms: 90 g water, 5 g carbohydrates, 3.5 g milk proteins, 3.5 g milk fat, vitamins and minerals.

What’s in a 100 ml glass of semi-skimmed milk?

Composition d'un verre de lait demi-écrémé (100ml)

 

 

Milk in different states

The main ingredients of milk are present in three different physical states:

  • Fats are emulsified with water
  • Proteins are suspended in water
  • Carbohydrates are dissolved in water

 

Why is milk white?

Milk appears white thanks to casein (a dominant protein in milk) and fat. These two ingredients reflect light, which is why milk is white.

But sometimes milk can have a hint of blue! Skimmed milk contains less fat and therefore fewer light-reflecting particles. Casein refracts more blue waves, which is why we see a hint of blue in skimmed milk.

 

Milk processing processes

The same methods as yesterday but with today's means


Milk produces a wide variety of dairy products, thanks to its rich ingredients, as well biological and physical processing methods.

Previous dairy methods have been conserved and optimized with the latest technology to offer ever more quality and guarantees.

2 types of processing methods

  • Biological: using micro-organisms (bacteria, starter cultures and fermenting agents)
  • Physical: using heat-action and skimming

Butter

Skimming:Milk is separated from the cream, which is used as the basis for butter.
Starter cultures and fermentation:Dairy cultures are added to the cream, which thickens.
Churning and creaming:The cream is beaten to obtain grains. These grains are then creamed.

 

 

 

 

 

 

Cream

Skimming and mixing:The cream is separated from the milk and its fat content adjusted.
Starter cultures and fermentation:Dairy cultures are added to the cream, which is left to ferment.
Packaging:The cream is added to pots. These pots are then refrigerated (at 4°C).

 

 

 

 

 

 

Yoghurt

Skimming and mixing:The cream is separated from the milk and the quantity of cream adjusted.
Starter cultures:Dairy cultures are added to make the product less liquid.
Packaging:Yoghurt is stored in pots with a sealed lid. These pots are then refrigerated (at 4°C).

Cheese

Skimming:Cream is separated from the milk and the quantity of cream adjusted.
Curdling:Dairy starter cultures and rennet are added to the milk to produce curds.
Moulding:Cheese is placed in moulds of different sizes. It is then removed from these moulds.
Maturation:Cheese matures in ageing cellars for different lengths of time depending on the type of cheese.

Drinking milk

With the exception of raw milk, all drinking milk undergoes skimming/standardization and thermal processing stages. These can vary in terms of the techniques used or occur in a different order depending on the type of milk.

Skimming and mixing:Cream is separated from the milk and its quantity adjusted (for skimmed milk, semi-skimmed milk or whole milk).
Heat treatment:Pasteurization, sterilization and/or microfiltration.
Packaging:In bottles or cartons (in aseptic conditions, in the dark, etc., as appropriate).

Powdered milk

Skimming:Cream is separated from the milk and the quantity of cream adjusted.
ConcentrationMilk passes through successive evaporators to become increasingly concentrated.
DryingThe spray-drying tower transforms concentrated milk into powder.

Ever more guarantees

Every effort is made to produce healthy, perfect milk: milk analyses on the farm and at every stage of processing, transparent labelling, the guarantees provided by PDOs and brands, etc. Between the role of the State and self-monitoring by the industry, milk processing is under high surveillance. Three key words sum it up: quality, food safety and transparency.

Quality across the entire value chain

Features of quality milk
 

  • Healthy
  • Guaranteed fat and protein content
  • Compliant with European hygiene standards

Standard composition of milk

  • Fat: 38 g/L
  • Protein: 32 g/L
  • Germs < 100,000 CFU/mL
  • Cells < 400,000 /mL
  • Absence of antibiotic residues and sulphonamides
  • No added water

Farmers: the first guarantors of milk quality

Farmers attend to the health and diet of their herds while ensuring spotless hygiene. These commitments are set out in the French Charter for Good Agricultural Practices. Some 90% of French cattle farmers have adopted this code. The price farmers receive for their milk also depends on quality.

Milk collection is rigorously organized

The milking shed and equipment are disinfected after each milking session. Milk is stored in a tank at 4°C to respect the cold chain, then transported in refrigerated lorries. Milk quality is controlled randomly at least three times a month in certified laboratories.

Milk is controlled again after arriving at the dairy

Milk samples are analysed. The milk undergoes physical treatments to eliminate micro-organisms. Traceability is ensured between the tank and the farms. No dairy product leaves the dairy without a quality guarantee.

Food safety above all

The French State and numerous bodies control the quality and safety of processed milk at every stage of the value chain.

  • Strict controls for food safety conditions

    On the farm, the application of the French Charter for Good Agricultural Practices is controlled to ensure correct animal feeding, perfect hygiene, etc. Farmers are also assisted by veterinarians, who monitor animal health.

     

  • Milk tested numerous times

    Cow’s milk is subject to rigorous controls. During milking, numerous samples are taken and analysed in a laboratory to ensure food safety. Upon arrival at the factory, milk is tested again as it is transferred from the tanker to the factory’s storage tank.

  • Milk processing under high surveillance

    To avoid altering milk quality during processing, the factory uses the Hazard Analysis and Critical Control Points (HACCP) method. This involves identifying, evaluating and managing risks. Control points are implemented throughout the value chain to ensure the safety of processed milk.

  • Safety guaranteed right to the store

    Chilled dairy products are sent to distributors in refrigerated lorries to respect the cold chain. In stores, distributors carry out controls in-house to check that the products are being stored well at the right temperature and that good hygiene practices are being used.

Transparent labelling

Little labels that say a lot

Labels provide information on the nutritional content and origins of dairy products.

For example:

  • Barcodes guaranteeing traceability
  • “Best before” date
  • Food safety approval number
  • Manufacturing batch number

Nutritional labelling for 2016

Optional up until now, seven labelling items will be compulsory under new European regulation. These are: calories, fat, saturated fat, carbohydrates, protein and salt.