Calcium sulfate
7778-18-9 · Anhydrite · Anhydrous calcium sulfate · Anhydrous gypsum · Anhydrous sulfate of lime · Anhydrous sulphate of lime · Artificial Dental Stone · Basic calcium sulfate · Calc Sulph · Calc Sulph 12X · Calc Sulph 14X · Calc Sulph 200X · Calc Sulph 30X · Calc Sulph 3X · Calc Sulph 6X · Calcarea Sulfurica · CALCAREA SULPH · Calcarea sulphurica · Calcarea Sulphurica 200ck · Calcarea sulphurica 30C · Calcii sulfas · Calcium (as sulfate) · Calcium salt of sulfuric acid · CALCIUM SULFATE · Calcium sulfate (1:1) · Calcium sulfate (1:1) dihydrate · Calcium sulfate (CaSO4) · Calcium sulfate, anhydrous · Calcium sulphate · Calcium sulphate anhydrous · CALCIUM SULPHATE ANHYDROUS (E516) · Calmatrix · CAS 20 · Crysalba · Dead-burned gypsum · Denka sigma 1000 · Dental Stone, Artificial · Drierite · E 516 · Franklin Fiber H 45 · GIBS · Gypsum · Gypsum, Dental · INS NO.516 · INS-516 · Insoluble anhydrite · Karstenite · Muriacite · Native calcium sulphate · Natural anhydrite · Oparex 10 · Osteoset · Precipitated calcium sulphate · Raddichem 27 · Selenite · Shi gao · Shigao · SSS-A · Stone paste · Stone, Artificial Dental · SULFURIC ACID CALCIUM(2+) SALT (1:1) · Sulfuric acid, calcium salt (1:1) · Thiolite · TONICPET 3 · E516 · 516 · Calcium sulfate · Calcium sulfate · Calcium sulphate · Calcium sulphate · Calciumsulfaat · Calciumsulfat · Kalcija sulfāts · Kalcijev sulfat · Kalcio sulfatas · Kalcium-szulfát · Kalciumsulfat · Kalsiumsulfaatti · Kaltsiumsulfaat · Siarczan wapnia · Solfato di calcio · Sulfat de calciu · Sulfat tal-kalċju · Sulfate de calcium · Sulfato cálcico · Sulfato de cálcio · SÍRAN VÁPENATÝ · Sírany vápenaté · Θειικό ασβέστιο · Калциев сулфатE number E516INS 516CAS 7778-18-9
Listed as an acidity regulator, a stabiliser and a firming agent by Canada, Codex and the US.
Listed as acidity regulators (CA, US, Codex) · stabilisers (CA, US, Codex) · firming agents (CA, US, Codex) · colours (US, Codex) · thickeners (CA, US) · flour treatment agents (US, Codex) · emulsifiers (CA) · raising agents (US) · anticaking agents (US) · sequestrants (Codex) · dough strengtheners (US) · nutrient supplements (US) · texturisers (US) · formulation aids (US) · lubricants and release agents (US) · synergists (US) · yeast foods (CA) · processing aids (US)
- Canada: Acidity regulator — Health Canada, List of Permitted Acidity Regulators and Acid-Reacting Materials (List 10)
- United States: pH control agent — FDA, Substances Added to Food: CALCIUM SULFATE
- United States: pH control agents — 21 CFR 184.1230, citing 21 CFR 170.3(o)(23)
- Codex Alimentarius: Acidity regulator — CXS 192-1995 Table One, INS 516
- Canada: Emulsifying, stabilizing or thickening agent — Health Canada, List of Permitted Emulsifying, Gelling, Stabilizing or Thickening Agents (List 4)
- Canada: Stabilizing agent — Health Canada, List of Permitted Emulsifying, Gelling, Stabilizing or Thickening Agents (List 4)
- United States: Stabilizer or thickener — FDA, Substances Added to Food: CALCIUM SULFATE
- United States: Stabilizers and thickeners — 21 CFR 184.1230, citing 21 CFR 170.3(o)(28)
- Codex Alimentarius: Stabilizer — CXS 192-1995 Table One, INS 516
- Canada: Firming agent — Health Canada, List of Permitted Firming Agents (List 6)
- United States: Firming agents — 21 CFR 184.1230, citing 21 CFR 170.3(o)(10)
- Codex Alimentarius: Firming agent — CXS 192-1995 Table One, INS 516
- United States: Colors and coloring adjuncts — 21 CFR 184.1230, citing 21 CFR 170.3(o)(4)
- Codex Alimentarius: Colour — CXS 192-1995 Table One, INS 516
- Canada: Emulsifying, stabilizing or thickening agent — Health Canada, List of Permitted Emulsifying, Gelling, Stabilizing or Thickening Agents (List 4)
- United States: Stabilizer or thickener — FDA, Substances Added to Food: CALCIUM SULFATE
- United States: Stabilizers and thickeners — 21 CFR 184.1230, citing 21 CFR 170.3(o)(28)
- United States: Flour treating agents — 21 CFR 184.1230, citing 21 CFR 170.3(o)(13)
- Codex Alimentarius: Flour treatment agent — CXS 192-1995 Table One, INS 516
- Canada: Emulsifying, stabilizing or thickening agent — Health Canada, List of Permitted Emulsifying, Gelling, Stabilizing or Thickening Agents (List 4)
- United States: Leavening agent — FDA, Substances Added to Food: CALCIUM SULFATE
- United States: Leavening agents — 21 CFR 184.1230, citing 21 CFR 170.3(o)(17)
- United States: Anticaking agent or free-flow agent — FDA, Substances Added to Food: CALCIUM SULFATE
- United States: Anticaking agents and free-flow agents — 21 CFR 184.1230, citing 21 CFR 170.3(o)(1)
- Codex Alimentarius: Sequestrant — CXS 192-1995 Table One, INS 516
- United States: Dough strengtheners — 21 CFR 184.1230, citing 21 CFR 170.3(o)(6)
- United States: Nutrient supplement — FDA, Substances Added to Food: CALCIUM SULFATE
- United States: Nutrient supplements — 21 CFR 184.1230, citing 21 CFR 170.3(o)(20)
- United States: Texturizers — 21 CFR 184.1230, citing 21 CFR 170.3(o)(32)
- United States: Formulation aid — FDA, Substances Added to Food: CALCIUM SULFATE
- United States: Formulation aids — 21 CFR 184.1230, citing 21 CFR 170.3(o)(14)
- United States: Lubricant or release agent — FDA, Substances Added to Food: CALCIUM SULFATE
- United States: Synergists — 21 CFR 184.1230, citing 21 CFR 170.3(o)(31)
- Canada: Yeast food — Health Canada, List of Permitted Yeast Foods (List 14)
- United States: Processing aid — FDA, Substances Added to Food: CALCIUM SULFATE
- United States: Processing aids — 21 CFR 184.1230, citing 21 CFR 170.3(o)(24)

Calcium sulfate, or gypsum, is a firming agent and the other common tofu coagulant, giving a softer curd than magnesium chloride. It is also used as a dough conditioner and calcium source.
Where it is and isn’t permitted
| Jurisdiction | Status | Scope and limits | Citation |
|---|---|---|---|
| Australia and New Zealand | Permitted, with conditions | 55 food categories no numerical limit (good manufacturing practice) Show every food category
| Food Standards Code, Schedule 15, S15—5and 54 further provisionsretrieved 2026-10-17 |
| Canada | Permitted, with conditions | highest permitted level 600 mg/kg 17 permitted uses Show every permitted use
| Health Canadaand 16 further provisionsretrieved 2026-10-17 |
| European Union | Permitted, with conditions | 68 food categories Show every food category
| Regulation (EC) No 1333/2008, Annex IIand 67 further provisionsretrieved 2026-10-18 |
| Great Britain | Permitted, with conditions | 66 food categories Show every food category
| Assimilated Regulation (EC) No 1333/2008, Annex II (as at 28 June 2024)and 65 further provisionsretrieved 2026-10-18 |
| Japan | Permitted, with conditions | Designated additive: Appended Table 1, item 454, 硫酸カルシウム (“Calcium Sulfate” in the unofficial English translation). …Designated additive: Appended Table 1, item 454, 硫酸カルシウム (“Calcium Sulfate” 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), entry 硫酸カルシウム: (1) [may be used only in the circumstances stated] “硫酸カルシウムは、食品の製造又は加工上必要不可欠な場合及び栄養の目的で使用する場合以外は食品に使用してはならない。” (2) [sets maximum levels of use for the foods stated; states an exception to the preceding sentence] “硫酸カルシウムの使用量は、カルシウムとして、食品の1.0%以下でなければならない。ただし、特別用途表示の許可又は承認を受けた場合は、この限りでない。” The Japanese is the standard as published. There is no official English translation of the Notification; 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 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), 황산칼슘 (“Calcium Sulfate”, the English the Code prints beside it); the Code marks it as also usable as a nutrient fortifier; 3. 영양강화제 (nutrient fortifiers), 황산칼슘; nutrient: 칼슘(Ca); the Code marks it as also usable as a general food additive. Main use (주용도) of 황산칼슘: 응고제, 산도조절제. Standard for use (사용기준) of 황산칼슘: (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 184.1230retrieved 2026-10-17 | |
| Codex Alimentarius | Permitted, with conditions | 8 food categories no numerical limit (good manufacturing practice) Show every food category and its notes
| CXS 192-1995 Table Three, INS 516and 8 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 | — | 55 GMP |
|---|---|---|
| Canada | 50 mg/kg – 600 mg/kg | 6 numeric limit, 5 GMP, 6 no quantity stated |
| European Union | — | 46 several limits, 22 no quantity stated |
| Great Britain | — | 66 quantum satis |
| Japan | — | 1 no quantity stated |
| South Korea | — | 1 no quantity stated |
| United States | — | 1 no quantity stated |
| Codex Alimentarius | — | 9 GMP |
What it is made from
Mined as gypsum and purified, or obtained as a by-product of industrial processes.
- Vegan
- Vegetarian
Compare other additives on the dietary indexes.
- CAS registry number
- 7778-18-9
- InChIKey
- OSGAYBCDTDRGGQ-UHFFFAOYSA-L
- PubChem
- CID 24497
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 % |
| Loss on drying | no more than 1.5 % | no more than 1.5 % |
| 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 516 Calcium sulphate
Synonyms: Gypsum; Selenite; Anhydrite
Assay, identification and purity criteria
Description and assay
- Einecs
- 231-900-3
- Chemical name
- Calcium sulphate
- Chemical formula
- CaSO₄ · nH₂O (n = 0 or 2)
- Molecular weight
- 136,14 (anhydrous), 172,18 (dihydrate)
- Assay
- Content not less than 99,0 % on the anhydrous basis
- Description
- Fine, white to slightly yellowish-white odourless powder
Identification
- Test for calcium
- Passes test
- Test for sulphate
- Passes test
- Solubility
- Slightly soluble in water, insoluble in ethanol
Purity criteria
- Loss on drying
- Anhydrous: not more than 1,5 % (250 °C, constant weight) Dihydrate: not more than 23 % (250 °C, constant weight)
- Fluoride
- Not more than 30 mg/kg
- Selenium
- Not more than 30 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 516 Calcium Sulfate
Synonyms: INS No. 516
Assay, identification and purity criteria
Description and assay
- Specification history
- Prepared at the 19th JECFA (1975), published in NMRS 55B (1976) and in FNP 52 (1992). Metals and arsenic specifications revised at the 63 rd JECFA (2004). ADI ‘not limited’ was established at the 17 th JECFA (1973).
- Chemical names
- Calcium sulfate
- C.A.S. number
- 7778-18-9
- Chemical formula
- Anhydrous: CaSO 4 Dihydrate: CaSO 4 · 2H 2 O
- Formula weight
- Anhydrous: 136.14 Dihydrate: 172.18
- Assay
- Not less than 99.0% after drying
- DESCRIPTION
- Fine, white to slightly yellow-white, odourless powder
- FUNCTIONAL USES
- Yeast food, dough conditioner, firming agent, sequestrant
Identification
- Solubility (Vol. 4)
- Slightly soluble in water; insoluble in ethanol
- Test for calcium (Vol. 4)
- Passes test
- Test for sulfate (Vol. 4)
- Passes test
Purity criteria
- Loss on drying (Vol. 4)
- Anhydrous: Not more than 1.5% (250 o to constant weight) Dihydrate: Between 19 and 23% (250 o to constant weight)
- Fluoride (Vol. 4)
- Not more than 30 mg/kg (Method I or III)
- Selenium (Vol. 4)
- Not more than 30 mg/kg Test 0.2 g of the sample as directed in the Limit Test Method II)
- 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.”
- METHOD OF
- Dissolve about 250 mg of the sample, accurately weighed, in 100 ml of water
- ASSAY
- and 4 ml of dilute hydrochloric acid TS, boil if necessary to effect solution, and cool. Add 15 ml of sodium hydroxide TS, 40 mg of murexide indicator preparation and 3 ml of naphthol green TS, and titrate with 0.05 M disodium ethylenediaminetetraacetate until the solution is deep blue in colour. Each ml of 0.05 M disodium ethylenediaminetetra-acetate is equivalent to 6.807 mg of CaSO 4 .
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
90 recorded names. A label may use any of them.
E number
- E516
INS number
- 516
CAS registry number
- 7778-18-9
As it appears in regulation
- Calcium sulfate
- Calcium sulphate
Other names
- Anhydrite
- Anhydrous calcium sulfate
- Anhydrous gypsum
- Anhydrous sulfate of lime
- Anhydrous sulphate of lime
- Artificial Dental Stone
- Basic calcium sulfate
- Calc Sulph
- Calc Sulph 12X
- Calc Sulph 14X
- Calc Sulph 200X
- Calc Sulph 30X
- Calc Sulph 3X
- Calc Sulph 6X
- Calcarea Sulfurica
- CALCAREA SULPH
- Calcarea sulphurica
- Calcarea Sulphurica 200ck
- Calcarea sulphurica 30C
- Calcii sulfas
- Calcium (as sulfate)
- Calcium salt of sulfuric acid
- CALCIUM SULFATE
- Calcium sulfate (1:1)
- Calcium sulfate (1:1) dihydrate
- Calcium sulfate (CaSO4)
- Calcium sulfate, anhydrous
- Calcium sulphate
- Calcium sulphate anhydrous
- CALCIUM SULPHATE ANHYDROUS (E516)
- Calmatrix
- CAS 20
- Crysalba
- Dead-burned gypsum
- Denka sigma 1000
- Dental Stone, Artificial
- Drierite
- E 516
- Franklin Fiber H 45
- GIBS
- Gypsum
- Gypsum, Dental
- INS NO.516
- INS-516
- Insoluble anhydrite
- Karstenite
- Muriacite
- Native calcium sulphate
- Natural anhydrite
- Oparex 10
- Osteoset
- Precipitated calcium sulphate
- Raddichem 27
- Selenite
- Shi gao
- Shigao
- SSS-A
- Stone paste
- Stone, Artificial Dental
- SULFURIC ACID CALCIUM(2+) SALT (1:1)
- Sulfuric acid, calcium salt (1:1)
- Thiolite
- TONICPET 3
Systematic names
- Calcium sulfate
Hazard reference values
| Type | Value | Population | Assessed by | Opinion |
|---|---|---|---|---|
| ADI | not limited | — | JECFA | 1973 |
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 sulphuric acid and its sodium, potassium, calcium and ammonium salts (E 513–E 517), noting exposure far below doses causing laxative effects in humans. It concluded that exposure does not raise a safety concern at reported uses and use levels and that no numerical ADI is needed.
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 516?
- E 516 is Calcium sulfate. Calcium sulfate, or gypsum, is a firming agent and the other common tofu coagulant, giving a softer curd than magnesium chloride. It is also used as a dough conditioner and calcium source.
- What is Calcium sulfate used for in food?
- It is listed as an acidity regulator, 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 Calcium sulfate 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 Calcium sulfate vegan?
- Yes. Calcium sulfate 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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