What is E626?
E626 is Guanylic acid, a food additive used as a flavour enhancer. Usually made from yeast or fermentation, but guanylates have also been made from fish or meat, and the pack does not say which. Same doubt as the inosinates (E630 to E635). Doubtful unless the product is vegan, vegetarian or halal-certified.
Also written as: INS 626, E-626, E 626. INS is the international numbering system used outside Europe, including on labels in Asia, Australia and the Middle East.
How E626 is made and where it is used
This section is food science. The religious classification is explained further down.
Guanylic acid is a flavour enhancer that boosts savoury flavour, often together with MSG.
It is mostly produced industrially by fermentation, with yeast or bacterial cultures grown on sugar or tapioca. It can also be extracted from yeast or from dried shiitake mushrooms, and it has also been made from fish and meat.
It is rare compared with its sodium salt E627.
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 E626 vegetarian or vegan?
Usually yes. It is normally made from yeast or by fermentation, though it has historically been made from fish or meat.
Why we classify it this way
Doubtful Usually made from yeast or fermentation, but guanylates have also been made from fish or meat, and the pack does not say which. Same doubt as the inosinates (E630 to E635). Doubtful unless the product is vegan, vegetarian or halal-certified.
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.
Guanylates are classified like the inosinates (E630 to E635): same possible sources, same unstated label.
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 E626 halal?
E626 (Guanylic acid) is doubtful (mushbooh). Usually made from yeast or fermentation, but guanylates have also been made from fish or meat, and the pack does not say which. Same doubt as the inosinates (E630 to E635). Doubtful unless the product is vegan, vegetarian or halal-certified.
What is E626 made from?
Usually yeast or fermentation; historically fish or meat.
What is E626 used for?
E626 is used as a flavour enhancer, typically in crisps, instant noodles, stock cubes and ready meals.
What should I do if a product contains E626?
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 E626 vegetarian or vegan?
Usually yes. It is normally made from yeast or by fermentation, though it has historically been made from fish or meat.