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

Other companies also use bacteria or fungi to produce casein.

From BBC • Jul. 12, 2025

For example, the main milk protein that is captured in the cheesemaking process is casein.

From Salon • Jul. 24, 2024

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

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

Hence, the great nutritive properties of buttermilk, which retains the casein in very large proportions, much of it being rejected by the butter in its separation from the cream.

From Domestic Animals History and description of the horse, mule, cattle, sheep, swine, poultry and farm dogs; with directions for their management, breeding, crossing, rearing, feeding, and preparation for a profitable market; also their diseases and remedies. Together with full directions for the management of the dairy. by Allen, Richard L.