Caramel IV (sulphite ammonia)
What you need to know
Caramel IV is the dark brown colour used in colas, soy sauce, gravies and many sauces. It is made by heating sugars with sulphite and ammonia compounds.
The process can leave a trace by-product called 4-methylimidazole (4-MEI). California lists 4-MEI as a possible carcinogen and sets a warning threshold, though major food regulators consider the levels in food safe.
It is purely cosmetic — it adds colour, not flavour or nutrition.
Where it stands, by region
The same additive can be approved in one country and banned in another. This is the divergence that matters most.
| 🇦🇺AU / NZ | Approved Permitted (FSANZ Food Standards Code). |
| 🇪🇺EU | Approved Permitted (EFSA). |
| 🇺🇸US | Approved Permitted; California Prop 65 sets a 4-MEI warning level, prompting reformulation by some makers. |
| 🇨🇦CA | Approved Permitted (Health Canada). |
Health evidence
How settled the science is for each area — not how dangerous. “Unknown” means not enough good studies yet.
Class IV caramel colour produced by heating carbohydrates with sulphite and ammonium compounds. Group ADI 200 mg/kg bw/day (JECFA); EFSA group ADI 300 mg/kg bw/day (2011). Trace contaminant: 4-methylimidazole (4-MEI).