ALSOFOUNDINCaramel Color (E150a)
Prop 65 ListedThe soda industry changed its recipe over one state's warning label. Also listed on labels as E150a, E150b, E150c, E150d, 4-MEI, Caramel colour.
E-number: E150
What it is
The most-used food coloring on earth by volume — made by heating carbohydrates, in four different classes. Classes III and IV are produced with ammonia compounds, and that process creates a byproduct called 4-methylimidazole, or 4-MEI. Your label says 'caramel color' either way.
Why it's in food
It's the brown in cola, soy sauce, gravy, bread crusts, beer, and pet food — cheap, stable, and expected. Without it, cola is a pale yellow liquid that nobody recognizes as cola.
US vs EU status
United States
FDA-approved and exempt from certification, with no requirement to say which class is in the bottle. Then California listed 4-MEI under Prop 65 in 2011, requiring a cancer warning above a daily threshold — and in 2012, rather than print warnings, Coca-Cola and PepsiCo reformulated their caramel color to cut 4-MEI. They did it nationally, quietly, with no announcement. Independent testing in 2014 still found wide variation between brands and regions.
European Union
Permitted as E150a–d with specified limits, and Europe's regulator re-evaluated the class in 2011, setting limits that constrain 4-MEI content in the ammonia-processed types. The European approach differs in one telling way: the class is identified by its own E number, so a European label distinguishes plain caramel from the ammonia-processed kind. An American label doesn't.
Common products
- Colas and root beer
- Soy sauce and Worcestershire sauce
- Gravies, broths, and packaged sauces
- Dark breads, pastries, and bagels
- Beer and dark spirits
- Pet food
Cleaner swaps
- Clear sodas and unsweetened seltzers
- Naturally brewed soy sauce (traditional, longer-aged)
- Breads browned by baking rather than by coloring
Case note
Two companies reformulated their most famous product in every state, rather than print a warning label required by one. That's the whole thesis of this library in a single episode: nobody needed a ban. They needed a sentence on a can, and they moved continents of syrup to avoid it.
FAQ
Isn't caramel color just burnt sugar?
Class I is close to that. Classes III and IV are made with ammonia compounds, which is where 4-MEI comes from — and those are the classes used in cola. Since a US label says only 'caramel color,' the difference between kitchen caramel and ammonia-processed industrial caramel is invisible at the shelf.
What is 4-MEI and why does California warn about it?
It's a byproduct of ammonia-processed caramel coloring. California added it to the Prop 65 list in 2011 after animal studies found tumors, setting a daily exposure threshold above which products need a cancer warning. Federal regulators consider dietary exposure low. One state disagreed enough to require a sign.
Did soda companies really change the formula?
Yes — in 2012 both major cola makers switched to a lower-4-MEI caramel coloring, and rolled it out nationwide rather than run two production lines. No recall, no press release, no label change. It's the cleanest proof on this board that a warning label can move an entire industry faster than a ban.
Can I tell which class is in my drink?
Not in the US — 'caramel color' covers all four. In Europe the E number identifies the class, so the ammonia-processed types are distinguishable on the label. Same additive family, two very different amounts of disclosure.
The Full File
The Caramel Color File
Four Colors. One Name.
How the FDA decides what reaches your table and your medicine cabinet — and how it learned to decide.
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