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 study found that diets rich in casein, the primary protein found in milk and cheese, along with wheat gluten, greatly reduced how much cholera bacteria could colonize the gut.

From Science Daily • Apr. 7, 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

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

From Salon • Jul. 24, 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.