Also known as: Disodium guanylate + Disodium inosinate mixture, Flavor nucleotides
Not Vegan
A mixture of E627 (disodium guanylate) and E631 (disodium inosinate). Both are typically derived from fish or meat.
Ingredient Data
Not Vegan
E635
Disodium guanylate + Disodium inosinate mixture; Flavor nucleotides
A mixture of E627 (disodium guanylate) and E631 (disodium inosinate). Both are typically derived from fish or meat.
Instant noodles, flavored chips, crackers, soups, seasoning blends.
Avoid unless confirmed plant or fermentation-derived by the manufacturer.
E635 is a shorthand for a combination of E627 and E631 used as an umami flavor booster. The animal origin is rarely declared. A reliable red flag on any 'vegan' processed snack.
In depth
Disodium 5'-ribonucleotides (E635) is not a single compound but a fixed blend of two flavor enhancers: disodium guanylate (E627) and disodium inosinate (E631), usually combined in roughly equal parts. Both are nucleotide salts, the sodium forms of naturally occurring nucleotides. On their own they have limited flavor impact, but they act synergistically with glutamates such as MSG (E621), amplifying perceived savory, umami taste well beyond what either delivers alone.
Because of this synergy, manufacturers frequently pair E635 with MSG in seasoning systems, allowing lower total quantities of flavor enhancer to 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 rather than flavor from the base ingredients themselves.
The vegan concern with E635 centers on inosinate (E631), which is commonly manufactured from animal tissue, historically from fish or meat. Inosinate is the nucleotide most associated with the savory taste of meat and fish, although this 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.
Both nucleotides can, in principle, be produced through bacterial fermentation of plant-based sugars, a route that 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. This ambiguity is why E635 is treated as not vegan by default rather than case by case.
E635 can appear under several names depending on the market. In the European Union it is typically written as 'disodium 5'-ribonucleotides' or the code E635. In the United States, E numbers are not used, so it 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, this means E635 functions as a flag to check with the manufacturer rather than a guarantee either way. Products marketed as vegetarian or vegan should have already sourced a plant or microbial version, but verification is prudent when the claim is absent.
The savory effect of E635 can be reproduced without animal-derived nucleotides. Fermentation-derived disodium inosinate and guanylate exist and are used in some vegan-certified products, 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, while 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
E635 is generally treated as not vegan because it contains disodium inosinate (E631), which is commonly derived from fish or meat. It can be made by fermentation from plant sugars, but the finished additive rarely states its origin. Unless the manufacturer confirms a plant or fermentation source, it should be considered animal-derived.
It is a blend of disodium guanylate (E627) and disodium inosinate (E631). Inosinate is often 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.
E635 works synergistically with glutamates like monosodium glutamate, greatly amplifying 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.
No. MSG (E621) is monosodium glutamate, while E635 is a mix of two nucleotide salts, guanylate and inosinate. They are different additives that are often used together because they enhance each other's savory effect. E635 raises the animal-origin concern that MSG usually does not.
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.