Caseinates are used as texturizers in ice cream, ice milk, sherbet, and frozen custard. They are also used as binders or extenders in some lunchmeats and soups and as a clarifying agent in wine.
Casein is a nutritive protein source found in many “protein” powders. Many people are allergic to milk and specifically to the casein molecule and therefore should avoid foods with added caseinates.
Casein is essentially nontoxic and is on the GRAS list.