Pronunciation: cā′sē-in, kā′sēn
1. The principal protein of cow's milk and the chief constituent of cheese. It is insoluble in water, soluble in dilute alkaline and salt solutions, forms a hard insoluble plastic with formaldehyde, and is used as a constituent of some glues; various components are designated α-, β-, and κ-caseins. β-Casein is converted to γ-casein by milk proteases. There are several isoforms of α-casein. κ-Casein is not precipitated by calcium ions.
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