casein

American  

[key-seen, -see-in, key-seen] / ˈkeɪ sin, -si ɪn, keɪˈsin /

noun

1. Biochemistry. a protein precipitated from milk, as by rennet, and forming the basis of cheese and certain plastics.

2. Fine Arts.

   1. an emulsion made from a solution of this precipitated protein, water, and ammonia carbonate.

   2. a paint in which this emulsion is used as a binder.

   3. a picture produced with this paint and emulsion.

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casein British  

/ -siːn, ˈkeɪsɪɪn /

noun

1. Also called (US): paracasein.  a phosphoprotein, precipitated from milk by the action of rennin, forming the basis of cheese: used in the manufacture of plastics and adhesives

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casein Scientific  

/ kā′sēn′,-sē-ĭn /

1. A white, tasteless, odorless mixture of related phosphoproteins precipitated from milk by rennin. Casein is very nutritious, as it contains all of the essential amino acids as well as all of the common nonessential ones. It is the basis of cheese and is used to make plastics, adhesives, paints, and foods.

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Etymology

Origin of casein

1835–45; < Latin cāse ( us ) cheese ¹ + -in ²

Example Sentences

See Examples For:

casein

In a recent study published in Polymers, researchers created a thin, flexible film using calcium caseinate, a commercially available form of casein, the primary protein found in milk.

From Science Daily ● Feb. 28, 2026

Once the casein is made through this precision fermentation, it is mixed with plant-based fat and the other components of milk needed for cheese, and then the traditional cheese-making process ensues.

From BBC ● Jul. 12, 2025

The fatty acid composition, phospholipid composition, and protein composition, including casein and whey protein genetic variations, were, in general, remarkably similar.

From Science Daily ● Mar. 27, 2024

"They obtained casein, the protein that's in milk… and using acid were able to break down the proteins into individual amino acids," explained Prof Green.

From BBC ● Jan. 1, 2024

If the content of casein and ash constituents is high, a higher degree of acidity will be reached than in a milk with a lower content.

From Outlines of dairy bacteriology A concise manual for the use of students in dairying by Edwin George Hastings