Calcium 5'-Ribonucleotides
The short version
A 1:1 calcium mixture of GMP and IMP — sodium-free analog of disodium 5'-ribonucleotides (E635).
It's widely considered safe at the amounts used in food, so we mark it green. The Safety section below has the details.
Where it comes from
A 1:1 mixture of calcium inosinate (E633) and calcium guanylate (E629), produced from yeast-RNA hydrolysis. The mixed nucleotide blend matches the umami profile of the more common disodium version (E635).
How it's used
The sodium-free analog of E635 — used in sodium-restricted savory blends and some infant cereals. Combined IMP + GMP synergize with glutamate even more strongly than either nucleotide alone, allowing lower total flavor-enhancer load.
Safety profile
ADI not specified (combined nucleotides).
Physical & chemical properties
White powder, sparingly soluble in water.
Regulation worldwide
Permitted globally with maximum-use limits per category.
Educational information only. Not medical or dietary advice.