What is whey



Whey is a by-product of cheese production and the extraction of casein. For the production of cheese, lactic acid bacteria or rennet enzyme are added to the milk for coagulation. Both of these cause the casein in the milk to curdle and the whey to separate from the cheese mass. When producing 1 kg of semi-hard cheese, for example, approx. 9 kg of whey are produced.

Depending on whether the milk-lactic acid bacteria (acid coagulation) or rennet enzyme (sweet coagulation) are used to coagulate the cheese, sour whey or sweet whey are obtained. There is also casein whey, which is obtained during the production of casein and which also belongs to the group of sour whey.

Ingredients of the whey varieties

Whey consists of around 96 percent water and around 6 percent dry matter. With more than 70 percent, the largest proportion of the dry matter of all types of whey consists of lactose, followed by protein and minerals. All three types of whey are almost fat-free and very low in calories.

The whey protein contained has a high biological value due to its high content of essential amino acids. The minerals and vitamins it contains also contribute to the health value of whey. It is rich in calcium, potassium and the water-soluble vitamins B2 and B12.

In the past, whey was seen as an undesirable by-product of cheese production and was mainly used in animal nutrition. Today, however, the high health value of whey has been recognized and there are numerous whey products and whey derivatives that play a major role in trade and the food industry. These include v. a .:

  • Drinking whey (Sour or sweet whey)
  • Mixed whey drinks: Drinking whey, which may contain additions of fruit concentrates, flavorings or sugar. They are therefore usually significantly more energetic than pure drinking whey.
  • Whey powder (Sour whey or sweet whey powder) is obtained by removing water from the whey and plays an important role in the food industry, where it is used for many different products, e.g. B: as sports food or in soups, confectionery and baked goods, meat products and dairy products. But whey powder is also used in the cosmetics industry.
  • lactose (Whey derivative) is obtained by crystallizing the whey and separating the other substances contained in the dry matter. Because of its biochemical properties, isolated lactose is an important raw material for many different branches of industry, such as B. in pharmacy, baby food or the food industry (as a binder or flavor carrier).


  • aid (2013): Milk and milk products, brochure from aid infodienst 1008/2013
  • State Association of the Dairy Industry North Rhine-Westphalia e.V. (www.dialog-milch.de)
  • Lexicon of Milk (1988), p. 258, Prof. Dr. Edmund Renner, Munich
  • Brochure: Commodity whey