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

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

Meanwhile, Those Vegan Cowboys is still focusing on easy-to-replace cheeses, like those on pizzas and burgers, while Standing Ovation says its casein can make a range of cheeses including camembert.

From BBC • Jul. 12, 2025

If New Culture's path toward convincing vegan cheese literally starts with casein, Climax's works backward from the magic ingredient.

From Salon • Aug. 19, 2024

A casein micelle-whey protein complex performed the best.

From Science Daily • Sep. 19, 2023

The proteins of milk consist of casein, which is insoluble, and albumen, which is soluble.

From Dietetics for Nurses by Proudfit, Fairfax T.