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

"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

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

Cheese contains a high concentration of the protein casein.

From Salon • Oct. 9, 2023

A casein micelle-whey protein complex performed the best.

From Science Daily • Sep. 19, 2023

The casein is dissolved to some extent and the remainder so changed, that it will remain in suspension for a long time in a finely divided form, after the curd has been broken up.

From Outlines of dairy bacteriology A concise manual for the use of students in dairying by Hastings, Edwin George