Sodium acid pyrophosphate
13446-24-7 · 14691-80-6 · 35405-51-7 · 7320-34-5 · 7722-88-5 · 7758-16-9 · Acid calcium pyrophosphate · Acid magnesium pyrophosphate · Calcium dihydrogen diphosphate · di-sodium dihydrogen pyrophosphate anhydrous · Dinatriumpyrophosphat · Diphosphoric acid, disodium salt · Diphosphoric acid, sodium salt (1:2) · Disodium acid pyrophosphate · Disodium dihydrogen diphosphate · Disodium dihydrogen pyrop hosphate · Disodium dihydrogen pyrophosphate · Disodium dihydrogenpyrophosphate · Disodium diphosphate · Disodium Diphosphate; Pyrophosphoric Acid Disodium Salt; Diphosphoric Acid Disodium Salt; Disodium Pyrophosphate; Disodium Acid Pyrophosphate; · disodium hydrogen (hydrogen phosphonatooxy)phosphonate · Disodium pyrophosphate · Disodiumpytophosphate · E 450(i) · E 450(ii) · E 450(iii) · E 450(ix) · E 450(v) · E 450(vii) · Grahamsches salz · H5WVD9LZUD · HSDB 377 · Magnesium dihydrogen diphosphate · magnesium diphosphate · magnesium pyrophosphate · Mono magnesium dihydrogen diphosphate · Monocalcium dihydrogen pyrop hosphate · monomagnesium dihydrogen pyrophosphate · Pyrophosphoric acid, disodium salt · SAPP · Sodium acid pyrophosphate · Sodium pyrophosphate (Na2H2P2O7) · Sodium pyrophosphate, dibasic · Tetrapotassium diphosphate · Tetrapotassium pyrophosphate · Tetrasodium diphosphate · Tetrasodium disphosphate · Tetrasodium phosphate · Tetrasodium pyrophosphate · Trisodium diphosphate · Trisodium monohydrogen diphosphate · Trisodium monohydrogen pyrophosphate · Trisodium pyrophosphate · E450 · 450(i) · 450(ii) · 450(iii) · 450(ix) · 450(v) · 450(vii) · Dimagnesium;phosphonato phosphate · Sodium acid pyrophosphateE number E450INS 450(i)CAS 7758-16-9
Used as an acidity regulator — Codex also lists it as emulsifier, emulsifying salt, humectant.
Sodium acid pyrophosphate is a raising agent in baking powders and refrigerated doughs, and is also used to stop potatoes greying after cutting.
Where it is and isn’t permitted
| Jurisdiction | Status | Scope and limits | Citation |
|---|---|---|---|
| United States | Permitted | 21 CFR 182.1087retrieved 2026-09-07 | |
| Codex Alimentarius | Permitted, with conditions | 108 food categories highest permitted level 44,000 mg/kg Show every food category
| CXS 192-1995 Table One, INS 450(i)and 107 further provisionsretrieved 2026-09-07 |
What it is made from
Made by heating monosodium phosphate, which drives out water and links two phosphate units. Different grades react at different speeds, which is how bakers control when a dough rises.
- Vegan
- Vegetarian
- CAS registry number
- 7758-16-9
- InChIKey
- GYQBBRRVRKFJRG-UHFFFAOYSA-L
- PubChem
- CID 24451
Every name it appears under
62 recorded names. A label may use any of them.
E number
- E450
INS number
- 450(i)
- 450(ii)
- 450(iii)
- 450(ix)
- 450(v)
- 450(vii)
CAS registry number
- 13446-24-7
- 14691-80-6
- 35405-51-7
- 7320-34-5
- 7722-88-5
- 7758-16-9
As it appears in regulation
- Sodium acid pyrophosphate
Other names
- Acid calcium pyrophosphate
- Acid magnesium pyrophosphate
- Calcium dihydrogen diphosphate
- di-sodium dihydrogen pyrophosphate anhydrous
- Dinatriumpyrophosphat
- Diphosphoric acid, disodium salt
- Diphosphoric acid, sodium salt (1:2)
- Disodium acid pyrophosphate
- Disodium dihydrogen diphosphate
- Disodium dihydrogen pyrop hosphate
- Disodium dihydrogen pyrophosphate
- Disodium dihydrogenpyrophosphate
- Disodium diphosphate
- Disodium Diphosphate; Pyrophosphoric Acid Disodium Salt; Diphosphoric Acid Disodium Salt; Disodium Pyrophosphate; Disodium Acid Pyrophosphate;
- disodium hydrogen (hydrogen phosphonatooxy)phosphonate
- Disodium pyrophosphate
- Disodiumpytophosphate
- E 450(i)
- E 450(ii)
- E 450(iii)
- E 450(ix)
- E 450(v)
- E 450(vii)
- Grahamsches salz
- H5WVD9LZUD
- HSDB 377
- Magnesium dihydrogen diphosphate
- magnesium diphosphate
- magnesium pyrophosphate
- Mono magnesium dihydrogen diphosphate
- Monocalcium dihydrogen pyrop hosphate
- monomagnesium dihydrogen pyrophosphate
- Pyrophosphoric acid, disodium salt
- SAPP
- Sodium acid pyrophosphate
- Sodium pyrophosphate (Na2H2P2O7)
- Sodium pyrophosphate, dibasic
- Tetrapotassium diphosphate
- Tetrapotassium pyrophosphate
- Tetrasodium diphosphate
- Tetrasodium disphosphate
- Tetrasodium phosphate
- Tetrasodium pyrophosphate
- Trisodium diphosphate
- Trisodium monohydrogen diphosphate
- Trisodium monohydrogen pyrophosphate
- Trisodium pyrophosphate
Systematic names
- Dimagnesium;phosphonato phosphate
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/sodium-acid-pyrophosphate.json