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

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

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

Cow's milk holds casein, one of the albuminoids, about five parts in one hundred; a fatty principle, when separated, known as butter, about four parts; sugar of milk four parts; water and salts eighty-seven parts.

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