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E400ThickenerLow concern
Alginic Acid
In plain words
The short version
A seaweed-derived polysaccharide used to thicken, stabilize, and form heat-stable gels with calcium.
Why it's green
It's widely considered safe at the amounts used in food, so we mark it green. The Safety section below has the details.
Safety profile
No ADI specified — regarded as safe. Not digested or absorbed; passes through the gut as soluble fiber. Very high intakes may modestly reduce mineral absorption.
The detail
Extracted from brown seaweeds (kelps such as Laminaria, Macrocystis, and Ascophyllum). A linear polysaccharide of mannuronic and guluronic acids, isolated industrially since the early 20th century.
Thickener, gelling agent, and stabilizer, and the parent of the alginate salts (E401–E405). Forms firm, heat-stable gels in the presence of calcium — used in restructured foods, sauces, and bakery fillings.
White-to-brownish fibrous powder. Insoluble in water but swells strongly; soluble and viscous as its sodium salt; gels with calcium ions.
Permitted in the EU. In the US it is affirmed as GRAS only for use in soups and soup mixes (21 CFR 184.1011). JECFA has set no numerical limit on intake (ADI not specified).
Sources
- EFSA ANS Panel — Re-evaluation of alginic acid and its sodium, potassium, ammonium and calcium salts (E 400–E 404) as food additives (2017), EFSA Journal 15(11):5049, doi:10.2903/j.efsa.2017.5049 — European Food Safety Authority, 2017. No ADI specified; regarded as safe
- WHO JECFA database — Alginic acid (INS 400) — World Health Organization / JECFA, 1992. ADI not specified (JECFA)
- 21 CFR 184.1011 — Alginic acid (GRAS affirmation) — U.S. eCFR / FDA, 1982. US status: GRAS limited to soups and soup mixes
- Commission Regulation (EU) No 1129/2011 establishing the Union list of food additives (Annex II to Regulation (EC) No 1333/2008) — EUR-Lex / European Union, 2011. EU authorisation (Group I, quantum satis)
Checked against these sources on .
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