E150c - Ammonia caramel
What it is and how it is used
Ammonia caramel is Class III caramel colour — one of four caramels distinguished not by shade but by what is used to make them. All four start by heating a food-grade carbohydrate; Class III is the one made in the presence of ammonium compounds, which produces a deep red-brown colour that is stable in the presence of protein and tolerates the tannins in beer.
That protein stability is precisely why it exists as a separate class. A caramel made without ammonia will flocculate and drop out of a beer or a gravy; Class III will not. It is the standard colour of British beer and of most brown sauces and gravies.
Foods commonly containing it
Beer and malt drinks, gravies and gravy granules, brown sauces, soy sauce, some breads and biscuits, pet food, and vinegars.
Safety summary
Ammonia caramel is authorised in Great Britain as E 150c, in Group II — food colours authorised at quantum satis.
EFSA re-evaluated the four caramel colours together in 2011 and set a group ADI of 300 mg per kg of body weight per day. Class III was given a lower individual ADI of 100 mg per kg of body weight per day within that group, because of information on the immunotoxicity of THI (2-acetyl-4-tetrahydroxybutylimidazole), a compound formed when ammonia is used in the process. The Panel concluded that anticipated dietary exposure for children and adults may exceed the ADIs for Classes I, III and IV.
Known concerns
The lower Class III ADI exists specifically because of THI, an imidazole by-product of the ammonia process with reported immunotoxicity. EFSA also flagged that anticipated exposure may exceed the ADI for this class — beer being the dominant contributor for adults.