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  

/ ˈkeɪsɪɪn, -siːn /

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

"Wheat gluten and casein are recognized as safe in a way a microbe is not, in a regulatory sense, so this is an easier way to protect public health," Hsiao said.

From Science Daily ● Apr. 7, 2026

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

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

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

From Salon ● Jul. 24, 2024

The casein and fatty substance are far more digestible in milk, than after they have been separated from it in the form of cheese and butter.

From A Treatise on Physiology and Hygiene For Educational Institutions and General Readers by Joseph Chrisman Hutchison