Yes, its safety when 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
SHMP is permitted to use as a flavoring agent or adjuvant in fruit jellies, cheese, frozen desserts and food dressing (6) (7). It is generally recognized as safe (GRAS) when used as a sequestrant in accordance with good manufacturing practice. (8)

EFSA
SHMP (E 452i) is a subclass of polyphosphates (E452) and classified in “additives other than colours and sweeteners”. It is approved as a food additive in the European Union (EU) in accordance with Annex II of Regulation (EC) No 1333/2008 on food additives and specific purity criteria have been defined in the Commission Regulation (EU) No 231/2012. (9)

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