Is E635 (Disodium 5'-ribonucleotides) Halal?

Our assessment

Doubtful — depends on source

E635 (Disodium 5'-ribonucleotides) is a blend of disodium guanylate (E627) and disodium inosinate (E631) whose sources can be microbial, fish or meat — so it is treated as doubtful (mushbooh) unless the source is known.

Also known asDisodium 5'-ribonucleotidesDisodium ribonucleotidesI+G

What is E635?

Disodium 5'-ribonucleotides is a very common flavour enhancer — a blend of E627 and E631 — used with MSG (E621) to boost savoury taste in snacks and instant foods. Like its components, it can be microbial, fish- or meat-derived.

Made by combining disodium guanylate and disodium inosinate, which can be produced by fermentation or derived from fish/meat. The source is almost never stated.

Why is it doubtful (mushbooh)?

E635 is doubtful because it inherits the source questions of E627 and E631 — microbial versions are permissible, fish- or meat-derived versions depend on the source (and fish matters to those avoiding it). Because it very commonly appears alongside E621 in snacks and its source is unstated, the honest default is to verify.

Commonly found in

It may be found in — this does not mean every product below contains it.

  • Savoury snacks and crisps
  • Instant noodles and seasonings
  • Stock cubes and ready meals
  • Processed savoury foods

How it appears on labels

Disodium 5'-ribonucleotidesE635Flavour enhancer (E635)

INS number: 635

How to verify a product in Singapore

  1. Ingredient-level guidance is not halal certification — check the complete product, not just this ingredient.
  2. Look for recognised halal certification, and check the finished product on the official MUIS HalalSG register.
  3. When the source or processing aids are unclear, contact the manufacturer.

In Singapore, verify the finished product on the MUIS HalalSG register or contact the manufacturer, since the source of E635 is usually not printed.

Check MUIS HalalSG

Sources: FAO/WHO, MUIS · Last reviewed: July 2026 · This guidance is not certification.

Frequently asked questions

Is E635 (disodium 5'-ribonucleotides) halal?

It is doubtful (mushbooh). It is a blend of E627 and E631, whose sources can be microbial, fish or meat and are usually unstated — verify with certification or the manufacturer.

Is E635 from pork?

Its components can be derived from meat (possibly including pork sources), but may also be microbial or fish. Confirm via certification or the manufacturer.

What names should I look for?

'Disodium 5'-ribonucleotides', 'E635' — usually listed with E621.

Related ingredients
Sources & methodology

Humble Halal methodology: we classify additives by their common origin, not by any specific product. A generally-halal ingredient does not make a finished product halal-certified. This page is general guidance, not certification or religious/legal advice — always verify the complete product. Last reviewed July 2026.