What is E634?
E634 is Calcium 5'-ribonucleotides, a food additive used as a flavour enhancer. A mix of inosinate and guanylate; the inosinate part can come from meat or fish.
Also written as: INS 634, E-634, E 634. INS is the international numbering system used outside Europe, including on labels in Asia, Australia and the Middle East.
How E634 is made and where it is used
This section is food science. The religious classification is explained further down.
Calcium 5'-ribonucleotides are a mix of calcium guanylate and calcium inosinate used as a flavour enhancer.
As for E627 and E631: fermentation or extraction from yeast, meat or fish.
It is rare in everyday foods.
What to do
Look for a halal logo, a "vegan" label, or a stated plant source on the pack. If none of these are present, you can contact the manufacturer and ask for the source.
Is E634 vegetarian or vegan?
Not always. E634 (Calcium 5'-ribonucleotides) can be made from plant or animal sources, and labels rarely say which. A vegetarian or vegan label on the pack confirms a plant or synthetic source.
Why we classify it this way
Doubtful A mix of inosinate and guanylate; the inosinate part can come from meat or fish.
Basis: Source or process not stated. It can be made from sources that change the ruling (for example pigs, an animal that was not slaughtered correctly, or alcohol), and the label does not say which.
References
- Resolution No. 210 (6/22): Transmutation and Dilution of Additives in Food and Medication, International Islamic Fiqh Academy (Organisation of Islamic Cooperation), 22 March 2015. Defines istihalah as a complete change into a different substance and says a partial change does not make a defiled substance pure. Adopts a 1995 IOMS fatwa that allows a slight amount of alcohol as a solvent for colours and preservatives, and alcohol on the skin, but says foods containing wine are not permitted even in a small ratio. Pig fat and pig rennet are prohibited; rennet from a correctly slaughtered animal is permitted; most participants hold rennet from an animal that was not slaughtered impure while some disagree; rennet made by genetic engineering is permitted. Pig heparin only under necessity. Gelatin was referred for further study with no ruling.
Classification audited 3 November 2026. It has not been reviewed by a scholar. How classifications work · Suggest a correction
Frequently asked questions
Is E634 halal?
E634 (Calcium 5'-ribonucleotides) is doubtful (mushbooh). A mix of inosinate and guanylate; the inosinate part can come from meat or fish.
What is E634 made from?
Meat or fish, or fermentation.
What is E634 used for?
E634 is used as a flavour enhancer, typically in crisps, instant noodles, stock cubes and ready meals.
What should I do if a product contains E634?
Look for a halal logo, a "vegan" label, or a stated plant source on the pack. If none of these are present, you can contact the manufacturer and ask for the source.
Is E634 vegetarian or vegan?
Not always. E634 (Calcium 5'-ribonucleotides) can be made from plant or animal sources, and labels rarely say which. A vegetarian or vegan label on the pack confirms a plant or synthetic source.