Calcium 5'-ribonucleotides

INS 634

Used as a flavour enhancer.

Calcium ribonucleotides are the mixed inosinate and guanylate salts, sold together because the two work better as a pair than either does alone.

Where it is and isn’t permitted

Status of Calcium 5'-ribonucleotides by jurisdiction. Every jurisdiction this site covers is listed, including those where the substance does not appear.
JurisdictionStatusScope and limitsCitation
United StatesFood and Drug AdministrationNot listedDoes not appear on this jurisdiction’s permitted list. That is not the same as being prohibited.
Codex AlimentariusCodex Alimentarius Commission / JECFAPermitted, with conditions

3 food categories

no numerical limit (good manufacturing practice)

Show every food category
  • 04.2.2.7 Fermented vegetable (including mushrooms and fungi, roots and tubers, pulses and legumes, and aloe vera) and seaweed products, excluding fermented soybean products of food categories 06.8.6, 06.8.7, 12.9.1, — GMP
  • 06.4.2 Dried pastas and noodles and like products — GMP
  • 12.1.2 Salt substitutes — GMP
CXS 192-1995 Table Three, INS 634and 3 further provisionsretrieved 2026-09-07

What it is made from

Made by neutralising a mixture of inosinic and guanylic acids, produced by fermentation or from yeast RNA, with calcium.

  • Vegan status depends on the source
  • Vegetarian status depends on the source
  • May raise a halal question
  • May raise a kosher question

This is not an omission. What this additive is made from is not fixed — depending on the manufacturer it may be plant, animal or microbial in origin, nobody is required to say which, and the same product can change source between production runs. Ask the manufacturer if it matters to you; a label cannot answer it.

InChIKey
LNMNHIIPGXAXIP-UHFFFAOYSA-L
PubChem
CID 171036373

Every name it appears under

2 recorded names. A label may use any of them.

INS number

  • 634

Other names

  • CALCIUM 5'-RIBONUCLEOTIDES

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

  • 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-5-ribonucleotides.json