Calcium sulfate

E number E516INS 516CAS 7778-18-9

Used as a colour — Codex also lists it as acidity regulator, firming agent, flour treatment agent, sequestrant, stabilizer.

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

Status of Calcium sulfate by jurisdiction. Every jurisdiction this site covers is listed, including those where the substance does not appear.
JurisdictionStatusScope and limitsCitation
United StatesFood and Drug AdministrationPermitted21 CFR 184.1230retrieved 2026-09-07
Codex AlimentariusCodex Alimentarius Commission / JECFAPermitted, with conditions

8 food categories

no numerical limit (good manufacturing practice)

Show every food category
  • 01.2.1.2 Fermented milks (plain), heat-treated after fermentation — GMP
  • 01.4.1 Pasteurized cream (plain) — GMP
  • 01.4.2 Sterilized and UHT creams, whipping and whipped creams, and reduced fat creams (plain) — GMP
  • 04.2.2.1 Frozen vegetables (including mushrooms and fungi, roots and tubers, pulses and legumes, and aloe vera), seaweeds and nuts and seeds — GMP
  • 06.2.1 Flours — GMP
  • 06.4.2 Dried pastas and noodles and like products — GMP
  • 10.2.1 Liquid egg products — GMP
  • 14.2.3.3 Fortified grape wine, grape liquor wine, and sweet grape wine — GMP
CXS 192-1995 Table Three, INS 516and 8 further provisionsretrieved 2026-09-07

What it is made from

Mined as gypsum and purified, or obtained as a by-product of industrial processes.

  • Vegan
  • Vegetarian
CAS registry number
7778-18-9
InChIKey
OSGAYBCDTDRGGQ-UHFFFAOYSA-L
PubChem
CID 24497

Every name it appears under

68 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

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

No reference value for this substance in the sources we hold.

Evidence and how bodies read it

Studies, and the differing conclusions regulators drew from them, are curated by hand rather than machine-read, and none has been written for this substance yet.

Sources for this page

  • ecfr retrieved 2026-09-07
  • gsfa retrieved 2026-09-07

Full licence terms and publisher details on Sources. How this page is built and updated: Method.

Machine-readable:/api/v1/additives/calcium-sulfate.json