Yes, its safety used as a food additive has been approved by the U.S. Food and Drug Administration (FDA), European Food Safety Authority (EFSA),  Joint FAO/WHO Expert Committee on Food Additives (JECFA), as well as other authorities.

FDA
Sodium caseinate is generally recognized as safe (GRAS) when used in accordance with good manufacturing practice (2) and can be used as an anticaking agent, emulsifier, flavoring agent, nutrient supplement, stabilizer or thickener and for other functions in food. (3)

JECFA
Function Class: food additives, emulsifier, stabilizer. (4)

Acceptable Daily Intake: ADI “not limited” set in 1970. (5)

 

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