Is Disodium 5'-Ribonucleotides (E635) Vegan?

Also known as: Disodium guanylate + Disodium inosinate mixture, Flavor nucleotides

Depends on Source

Last checked 10 Sept 2026 How we decide Edited by Anna Polovnikova

Disodium 5'-ribonucleotides depend on how they were made. E635 is a blend of E627 and E631. The leading producers report making both by microbial fermentation on plant-based media, and fish and meat routes also exist. On any snack marketed as plant-based, a vegan mark or the manufacturer's statement confirms the origin, which the label almost never declares.

Which animal, and does it die

Comes from: fish or meat animals, via extracts
Requires slaughter: Yes

Vegetarian depends on the source

From a mammalRelevant to alpha-gal syndrome
Fish-derivedRelevant to a fish allergy

These flags describe sourcing. They are not an allergen assessment, and a vegan label is not a free-from claim. If you have an allergy, read the allergen declaration on the pack.

Ingredient Data

Vegan Status

Depends on Source

E-Number

E635

Also Known As

Disodium guanylate + Disodium inosinate mixture; Flavor nucleotides

Source

A mixture of E627 (disodium guanylate) and E631 (disodium inosinate). The leading producers report making both by microbial fermentation on plant-based media, and fish and meat routes also exist.

Commonly Found In

Instant noodles, flavored chips, crackers, soups, seasoning blends.

Vegan Alternative

Avoid unless confirmed plant or fermentation-derived by the manufacturer.

Additional Notes

E635 is a shorthand for a combination of E627 and E631 used as an umami flavor booster. The origin is rarely declared. On any processed snack sold as vegan, a certification mark or the manufacturer's statement confirms which route was used.

In depth

What E635 actually is

Disodium 5'-ribonucleotides (E635) is a fixed blend of two flavor enhancers: disodium guanylate (E627) and disodium inosinate (E631). The blend is roughly equal parts. Both are nucleotide salts, the sodium forms of naturally occurring nucleotides. On their own they have limited flavor impact. With glutamates such as MSG (E621) they act synergistically, amplifying perceived savory, umami taste well beyond what either delivers alone.

Because of this synergy, manufacturers frequently pair E635 with MSG in seasoning systems. Lower total quantities of flavor enhancer then achieve a strong savory effect. The blend is valued in dry mixes, coatings, and broths where a rounded, meaty depth is desired. Its presence on a label almost always signals an engineered savory profile.

Where the raw material comes from

The vegan concern with E635 centers on inosinate (E631), which can be manufactured from animal tissue such as fish or meat. Inosinate is the nucleotide most associated with the savory taste of meat and fish. That flavor effect comes from the compound itself and is the same regardless of how it is produced. Guanylate (E627) is more often produced by microbial fermentation or from yeast extract, but it is sold as part of the blended E635 product.

The leading producers report making both nucleotides through microbial fermentation on plant-based media. That route avoids animal inputs entirely. However, the finished ingredient rarely states which process was used. Unless a manufacturer explicitly confirms a fermentation or plant origin, the source cannot be assumed. That ambiguity is why the verdict for E635 depends on the source.

Reading it on a label

E635 goes by different names in different markets. In the European Union it is typically written as 'disodium 5'-ribonucleotides' or the code E635. E numbers are not used in the United States. The blend shows up spelled out as 'disodium inosinate,' 'disodium guanylate,' or 'disodium 5'-ribonucleotides,' often listed immediately after monosodium glutamate.

Seeing E635 alongside MSG is the most common pattern, since the two are formulated together. The label almost never notes whether the inosinate came from fish, meat, or fermentation. For anyone avoiding animal products, E635 therefore functions as a flag to check with the manufacturer. Products marketed as vegetarian or vegan should have already sourced a plant or microbial version. Verification is prudent when the claim is absent.

Alternatives and how they compare

The savory effect of E635 can be reproduced without animal-derived nucleotides. Fermentation-derived disodium inosinate and guanylate exist. Some vegan-certified products use them, delivering the same umami synergy with glutamates. When a manufacturer confirms this origin, the additive becomes suitable for plant-based diets.

Whole-food sources of umami offer another route. Dried shiitake mushrooms are naturally rich in guanylate. Tomatoes, seaweed such as kombu, yeast extract, miso, soy sauce, and nutritional yeast supply glutamates and related savory compounds. Combining a glutamate source with a mushroom-based guanylate source recreates much of the same depth that E635 provides in processed foods. These options trade the precision and shelf stability of a purified additive for ingredients that are unambiguously plant based and require no origin verification.

Frequently asked questions

Is E635 vegan?

E635 depends on how it was made. The blend contains disodium inosinate (E631), which can be derived from fish or meat. Fermentation from plant sugars can make it. The finished additive rarely states its origin. A vegan certification mark or the manufacturer's statement can confirm a plant or fermentation source.

What is disodium 5'-ribonucleotides made from?

Disodium 5'-ribonucleotides is a blend of disodium guanylate (E627) and disodium inosinate (E631). Inosinate can be produced from animal tissue such as fish, while guanylate frequently comes from yeast or fermentation. Both can also be made microbially from plant-based sugars, but the label typically does not specify which process was used.

Why is E635 almost always listed next to MSG?

E635 works synergistically with glutamates like monosodium glutamate. The pairing greatly amplifies umami taste. Manufacturers pair them so that a smaller total amount of flavor enhancer produces a strong savory effect. Seeing the two together on an ingredient list is a normal formulation pattern.

Is E635 the same as MSG?

No. MSG (E621) is monosodium glutamate, while E635 is a mix of two nucleotide salts, guanylate and inosinate. They are different additives. They are often used together because they enhance each other's savory effect. E635 raises the animal-origin concern that MSG usually does not.

What can I use instead of E635 for umami flavor?

Whole-food umami sources work well. Dried shiitake mushrooms provide guanylate, while tomatoes, kombu seaweed, soy sauce, miso, and nutritional yeast supply glutamates. Combining a mushroom source with one of these recreates much of the savory depth of E635. Fermentation-derived nucleotides confirmed as plant-based are another option in packaged foods.