E 405 Propane-1,2-diol alginate – EU specification

COMMISSION REGULATION (EU) No 231/2012 of 9 March 2012


Hydroxypropyl alginate; 1,2-Propanediol ester of alginic acid; Propylene glycol alginate



Chemical name: 1,2-Propanediol ester of alginic acid; varies in composition according to its degree of esterification and the percentage of free and neutralised carboxyl groups in the molecule

Chemical formula: (C 9 H 14 O 7 ) n (esterified)

Molecular weight: 10 000-600 000 (typical average)

Assay: Yields, on the anhydrous basis, not less than 16 % and not more than 20 % of carbon dioxide (CO 2)


Nearly odourless, white to yellowish brown fibrous or granular powder


Test for 1,2-propanediol:  Passes test (after hydrolysis)

Test for alginic acid: Passes test (after hydrolysis)


Loss on drying: Not more than 20 % (105 °C, 4 hours)

Total propane-1,2-diol content: Not less than 15 % and not more than 45 %

Free propane-1,2-diol content: Not more than 15 %

Water insoluble matter: Not more than 2 % on the anhydrous basis

Formaldehyde: Not more than 50 mg/kg

Arsenic: Not more than 3 mg/kg

Lead: Not more than 5 mg/kg

Mercury: Not more than 1 mg/kg

Cadmium: Not more than 1 mg/kg

Microbiological criteria

Total plate count: Not more than 5 000 colonies per gram

Yeast and moulds: Not more than 500 colonies per gram

Escherichia coli: Absent in 5 g

Salmonella spp.: Absent in 10 g