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

The process starts with yeast that has been genetically modified to produce casein, the key protein in milk, instead of alcohol.

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

Cheese contains a high concentration of the protein casein.

From Salon • Oct. 9, 2023

Bentonite clay, gelatin, egg albumin from egg whites, purified milk proteins called casein and isinglass made from the bladders of sturgeons, are all used to filter the wine through a process called “fining.”

From National Geographic • Jul. 20, 2023

As a rule the casein and whey are in proportion of 1:1.

From Dietetics for Nurses by Proudfit, Fairfax T.