Magnesium chloride
17638-61-8 · 56491-84-0 · 7786-30-3 · Aerotex Accelerator MX · Anhydrous magnesium chloride · Bestmade Natural Products Mag Mur · Bischofite · Bischofite (mgcl2.6h2o) · Chloride, Magnesium · Chloromagnesite · Cramp-Z · E 511 · Fibro Flex · GZE Magnesium Oil · INS NO.511 · INS-511 · Magnesia Muriatica · Magnesium chloride · Magnesium chloride (Mg2Cl4) · Magnesium chloride (MgCl2) · Magnesium chloride anhydrous · Magnesium chloride solution 2M in water (19.2 - 20%wt) · Magnesium chloride, dry, 99.99% trace metals grade -10 Mesh beads · Magnesium Chloride, Powder · Magnesium Chloride, Powder, < 200um · Magnesium dichloride · magnesium(II)chloride · Magnesiumchlorid · magnesiumchloride · MgCl2 · MultiBic component magnesium chloride hexahydrate · Reagecon Magnesium Chloride 0.01M according to United States Pharmacopoeia (USP) · TMT 2 · E0183 · E511 · 511 · Magnesium dichloride · Reagecon Magnesium Chloride 0.1M according to European Pharmacopoeia (EP) Chapter 4 (4.2.2) · Magnesium chloride · Chlorek magnezu · Chlorid hořečnatý · Chlorure de magnésium · Cloreto de magnésio · Cloruro di magnesio · Cloruro magnésico · Clorură de magneziu · Klorur tal-manjeżju · Magneesiumkloriid · Magnesium chloride · Magnesiumchlorid · Magnesiumchloride · Magnesiumklorid · Magnesiumkloridi · Magnezijev klorid · Magnija hlorīds · Magnio chloridas · Magnézium-klorid · Χλωριούχο μαγνήσιο · Магнезиев хлоридE number E511INS 511CAS 7786-30-3
Listed as a stabiliser and a firming agent by Canada, Codex and the US.
Listed as stabilisers (CA, Codex) · firming agents (US, Codex) · colours (US) · emulsifiers (CA) · thickeners (CA) · colour retention agents (Codex) · nutrient supplements (US) · flavouring agents and adjuvants (US)
- Canada: Emulsifying, stabilizing or thickening agent — Health Canada, List of Permitted Emulsifying, Gelling, Stabilizing or Thickening Agents (List 4)
- Codex Alimentarius: Stabilizer — CXS 192-1995 Table One, INS 511
- United States: Firming agent — FDA, Substances Added to Food: MAGNESIUM CHLORIDE
- Codex Alimentarius: Firming agent — CXS 192-1995 Table One, INS 511
- United States: Color or coloring adjunct — FDA, Substances Added to Food: MAGNESIUM CHLORIDE
- Canada: Emulsifying, stabilizing or thickening agent — Health Canada, List of Permitted Emulsifying, Gelling, Stabilizing or Thickening Agents (List 4)
- Canada: Emulsifying, stabilizing or thickening agent — Health Canada, List of Permitted Emulsifying, Gelling, Stabilizing or Thickening Agents (List 4)
- Codex Alimentarius: Colour retention agent — CXS 192-1995 Table One, INS 511
- United States: Nutrient supplement — FDA, Substances Added to Food: MAGNESIUM CHLORIDE
- United States: Nutrient supplements — 21 CFR 184.1426, citing 21 CFR 170.3(o)(20)
- United States: Flavoring agent or adjuvant — FDA, Substances Added to Food: MAGNESIUM CHLORIDE
- United States: Flavoring agents and adjuvants — 21 CFR 184.1426, citing 21 CFR 170.3(o)(12)

Magnesium chloride is a firming agent and a traditional coagulant for tofu, setting soy milk into curd. It is the main component of nigari, the Japanese coagulant recovered from seawater.
Where it is and isn’t permitted
| Jurisdiction | Status | Scope and limits | Citation |
|---|---|---|---|
| Australia and New Zealand | Permitted, with conditions | 54 food categories no numerical limit (good manufacturing practice) Show every food category
| Food Standards Code, Schedule 15, S15—5and 53 further provisionsretrieved 2026-10-17 |
| Canada | Permitted, with conditions | highest permitted level 3,000 mg/kg 2 permitted uses Show every permitted use
| Health Canadaand 1 further provisionretrieved 2026-10-17 |
| European Union | Permitted, with conditions | 69 food categories Show every food category
| Regulation (EC) No 1333/2008, Annex IIand 68 further provisionsretrieved 2026-10-18 |
| Great Britain | Permitted, with conditions | 67 food categories Show every food category
| Assimilated Regulation (EC) No 1333/2008and 66 further provisionsretrieved 2026-10-18 |
| Japan | Permitted, with conditions | Designated additive: Appended Table 1, item 89, 塩化マグネシウム (“Magnesium Chloride” in the unofficial English translation). …Designated additive: Appended Table 1, item 89, 塩化マグネシウム (“Magnesium Chloride” in the unofficial English translation). Standards for use — Specifications and Standards for Foods, Food Additives, etc. (MHW Notification No. 370 of 1959), Part II (Food Additives), F (Standards for use): The Notification sets no standard for use (使用基準) for this additive, so it is not restricted there to particular foods or amounts. Compositional specifications for this additive, in the same Notification, are not imported and are not shown here; nor are the general rules in F 添加物一般, which apply to every additive. | Regulations for Enforcement of the Food Sanitation Act (MHW Ordinance No. 23 of 1948), Appended Table 1retrieved 2026-10-18 |
| South Korea | Permitted, with conditions | Designated food additive: Standards and Specifications for Food Additives, Part III, 1. …Designated food additive: Standards and Specifications for Food Additives, Part III, 1. 일반식품첨가물 (general food additives), 염화마그네슘 (“Magnesium Chloride”, the English the Code prints beside it); the Code marks it as also usable as a nutrient fortifier; 3. 영양강화제 (nutrient fortifiers), 염화마그네슘; nutrient: 마그네슘 (Mg); the Code marks it as also usable as a general food additive. Main use (주용도) of 염화마그네슘: 응고제. Standard for use (사용기준) of 염화마그네슘: (1) [to be used under the general standard for use in II. 2. 1), the minimum amount that achieves the technical effect, with no limit set for this additive in particular] “II. 2. 1)의 규정에 따라 사용하여야 한다.” The Korean is the standard as published. There is no official English translation of the current Code (the English version on MFDS’s website is the 2020 edition and has no legal effect); the English in square brackets is this site’s description of what each sentence does, not a translation of the foods or the levels. Compositional specifications (Part IV) are not imported, nor are the general standards in Part II, which apply to every additive. | Standards and Specifications for Food Additives (식품첨가물의 기준 및 규격), MFDS Notification, Part III (Standards for use, by item)retrieved 2026-10-18 |
| United States | Permitted | 21 CFR 184.1426retrieved 2026-10-17 | |
| Codex Alimentarius | Permitted, with conditions | 14 food categories no numerical limit (good manufacturing practice) Show every food category and its notes
| CXS 192-1995 Table Three, INS 511and 14 further provisionsretrieved 2026-09-07 |
How much is permitted
A listing usually limits the quantity as well as the food. Only one of the forms that takes is a figure: quantum satis and good manufacturing practice permit the amount the technological effect requires and no more, which is a limit rather than the absence of one. Figures below are the range across every food category this page is listed in, and categories differ between regulators — see how much is permitted.
| Australia and New Zealand | — | 54 GMP |
|---|---|---|
| Canada | 3,000 mg/kg | 1 numeric limit, 1 GMP |
| European Union | — | 46 several limits, 1 quantum satis, 22 no quantity stated |
| Great Britain | — | 67 quantum satis |
| Japan | — | 1 no quantity stated |
| South Korea | — | 1 no quantity stated |
| United States | — | 1 no quantity stated |
| Codex Alimentarius | — | 15 GMP |
What it is made from
Recovered from seawater or from brines after other salts are removed.
- Vegan
- Vegetarian
Compare other additives on the dietary indexes.
- CAS registry number
- 7786-30-3
- InChIKey
- TWRXJAOTZQYOKJ-UHFFFAOYSA-L
- PubChem
- CID 5360315
The two specifications, compared
The European Union sets identity and purity by regulation; JECFA publishes its own through FAO, advisory until a country adopts it. Both documents are below in full. These are the parameters each puts a number on.
| Parameter | European Union | JECFA |
|---|---|---|
| Assay | no less than 99 % | no less than 99 % |
| Lead | no more than 2 mg/kg | no more than 2 mg/kg |
| Arsenic | no more than 3 mg/kg | — |
| Mercury | no more than 1 mg/kg | — |
The two documents state the same figures for every parameter compared here.
How the EU defines it
The legal specification an additive must meet to be sold as this E number in the EU — what it is, how it may be made, and the purity it must reach. From Commission Regulation (EU) No 231/2012.
E 511 Magnesium chloride
Assay, identification and purity criteria
Description and assay
- Einecs
- 232-094-6
- Chemical name
- Magnesium chloride
- Chemical formula
- MgCl₂ · 6H₂O
- Molecular weight
- 203,30
- Assay
- Content not less than 99,0 %
- Description
- Colourless, odourless, very deliquescent flakes or crystals
Identification
- Test for magnesium
- Passes test
- Test for chloride
- Passes test
- Solubility
- Very soluble in water, freely soluble in ethanol
Purity criteria
- Ammonium
- Not more than 50 mg/kg
- Arsenic
- Not more than 3 mg/kg
- Lead
- Not more than 2 mg/kg
- Mercury
- Not more than 1 mg/kg
How JECFA defines it
The international specification for identity and purity, prepared by the Joint FAO/WHO Expert Committee on Food Additives and published by FAO. It is a different document from any above, written by a different body and revised on its own cycle; it is advisory, and a country adopts it or does not.
INS 511 Magnesium Chloride
Synonyms: INS No. 511
Assay, identification and purity criteria
Description and assay
- Specification history
- Prepared at the 27th JECFA (1983), published in FNP 28 (1983) and in FNP 52 (1992). Metals and arsenic specifications revised at the 63rd JECFA (2004). An ADI 'Not limited' was established at the 23rd JECFA (1979).
- Chemical names
- Magnesium chloride hexahydrate
- C.A.S. number
- 7786-30-3
- Chemical formula
- MgCl2 · 6H2O
- Formula weight
- 203.30
- Assay
- Not less than 99.0% and not more than 105.0%
- DESCRIPTION
- Colourless, odourless flakes, granules, lumps or crystals; it is very deliquescent
- FUNCTIONAL USES
- Firming agent, colour retention agent
- METHOD OF ASSAY
- Dissolve about 450 mg of the sample, accurately weighed, in 25 ml of water, add 5 ml of ammonia/ammonium chloride buffer TS and 0.1 ml of eriochrome black TS and titrate with 0.05 M disodium ethylenediaminetetraacetate until the solution is blue in colour. Each ml of 0.05 M disodium ethylenediaminetetra-acetate is equivalent to 10.16 mg of MgCl2 · 6H2O.
Identification
- Solubility (Vol. 4)
- Very soluble in water; freely soluble in ethanol
- Test for chloride (Vol. 4)
- Passes test
- Test for magnesium (Vol. 4)
- Passes test
Purity criteria
- Ammonium
- Not more than 50 mg/kg Dissolve 1 g of the sample in 90 ml of water, and slowly add 10 ml of a freshly boiled and cooled solution of sodium hydroxide (1 in 10 soln). Allow to settle, then decant 20 ml of the supernatant liquid into a colour comparison tube, dilute to 50 ml with water, and add 2 ml of Nessler's TS. Any colour does not exceed that produced by 10 μg of ammonium (NH4) ion in 48 ml of water and 2 ml of the sodium hydroxide solution.
- Lead (Vol. 4)
- Not more than 2 mg/kg Determine using an atomic absorption technique appropriate to the specified level. The selection of sample size and method of sample preparation may be based on the principles of the method described in Volume 4, “Instrumental Methods.”
Authorised in other additives, enzymes, flavourings and nutrients
These authorisations are not for use in food. They let this substance be used inside another additive, a food enzyme, a flavouring or a nutrient preparation — often as a carrier — and it reaches food only as part of that product. Annex III to Regulation (EC) No 1333/2008.
| Part | May be used in | Maximum level | Citation |
|---|---|---|---|
| Annex III, Part 1: Carriers in food additives | All food additives | quantum satis | Regulation (EC) No 1333/2008, Annex III, Part 1 |
| Annex III, Part 2: Food additives other than carriers in food additives | All food additive preparationsAuthorised as a member of Table 1 of Part 6, listed as "Table 1" Note (1): Except enzymes authorised as food additives. | quantum satis | Regulation (EC) No 1333/2008, Annex III, Part 2, via Table 1 of Part 6 |
| Annex III, Part 3: Food additives including carriers in food enzymes | Food enzymesCan be used as a carrier: Yes Note (1): Including enzymes authorised as food additives. | In enzyme preparation: quantum satis In final food except beverages: quantum satis In beverages: quantum satis | Regulation (EC) No 1333/2008, Annex III, Part 3 |
| Annex III, Part 4: Food additives including carriers in food flavourings | All flavouringsAuthorised as a member of Table 1 of Part 6, listed as "Table 1" | quantum satis | Regulation (EC) No 1333/2008, Annex III, Part 4, via Table 1 of Part 6 |
| Annex III, Part 5, Section A: Food additives added in nutrients except in nutrients intended to be used in foodstuffs listed in Part E, point 01.10, of Annex II and foodstuffs for infants and young children listed in Part E, point 13.1, of Annex II | All nutrients | quantum satis | Regulation (EC) No 1333/2008, Annex III, Part 5, Section A |
Every name it appears under
59 recorded names. A label may use any of them.
E number
- E0183
- E511
INS number
- 511
CAS registry number
- 17638-61-8
- 56491-84-0
- 7786-30-3
As it appears in regulation
- Magnesium chloride
Other names
- Aerotex Accelerator MX
- Anhydrous magnesium chloride
- Bestmade Natural Products Mag Mur
- Bischofite
- Bischofite (mgcl2.6h2o)
- Chloride, Magnesium
- Chloromagnesite
- Cramp-Z
- E 511
- Fibro Flex
- GZE Magnesium Oil
- INS NO.511
- INS-511
- Magnesia Muriatica
- Magnesium chloride
- Magnesium chloride (Mg2Cl4)
- Magnesium chloride (MgCl2)
- Magnesium chloride anhydrous
- Magnesium chloride solution 2M in water (19.2 - 20%wt)
- Magnesium chloride, dry, 99.99% trace metals grade -10 Mesh beads
- Magnesium Chloride, Powder
- Magnesium Chloride, Powder, < 200um
- Magnesium dichloride
- magnesium(II)chloride
- Magnesiumchlorid
- magnesiumchloride
- MgCl2
- MultiBic component magnesium chloride hexahydrate
- Reagecon Magnesium Chloride 0.01M according to United States Pharmacopoeia (USP)
- TMT 2
Systematic names
- Magnesium dichloride
- Reagecon Magnesium Chloride 0.1M according to European Pharmacopoeia (EP) Chapter 4 (4.2.2)
Hazard reference values
| Type | Value | Population | Assessed by | Opinion |
|---|---|---|---|---|
| ADI | not limited | — | JECFA | 1979 |
Evidence and how bodies read it
What assessing bodies concluded
Each conclusion is paraphrased in the body's own framing, from the published opinion linked beneath it. Where bodies differ, both stand; this site does not adjudicate between them or add a view of its own.
EFSA 2019
The FAF Panel found no concern for genotoxicity or carcinogenicity for hydrochloric acid and its potassium, calcium and magnesium salts (E 507–E 509, E 511), and used a human reference value of 40 mg chloride/kg bw/day. Although high-percentile exposure in toddlers, children and adolescents was slightly above that value, it concluded that exposure to chloride from these additives does not raise a safety concern at reported uses.
Common questions
Assembled from what is above, in the words the questions are usually asked in. Each answer is the same statement the relevant section makes, with the same citations behind it.
- What is E 511?
- E 511 is Magnesium chloride. Magnesium chloride is a firming agent and a traditional coagulant for tofu, setting soy milk into curd. It is the main component of nigari, the Japanese coagulant recovered from seawater.
- What is Magnesium chloride used for in food?
- It is listed as a stabiliser and a firming agent — the role Canada, Codex and the US assign it. This page shows every function each regulator records, with the citation for each.
- Where is Magnesium chloride permitted?
- Of the seven regulators this site reads, Australia and New Zealand, Canada, the EU, Great Britain, Japan, South Korea, the US and the Codex standard permit it. Each permission is for named foods at named levels, not a blanket one; the table on this page gives them with citations.
- Is Magnesium chloride vegan?
- Yes. Magnesium chloride is not derived from animals, and is suitable for vegetarians. This page says what it is made from and how.
Sources for this page
- anz retrieved 2026-10-17
- ca retrieved 2026-10-17
- eu retrieved 2026-10-18
- gb retrieved 2026-10-18
- jp retrieved 2026-10-18
- kr retrieved 2026-10-18
- ecfr retrieved 2026-10-17
- gsfa retrieved 2026-09-07
- euspecs retrieved 2026-10-18
- jecfaspecs retrieved 2026-09-23
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