"Is caramel color the same as caramel?"

"No. Caramel (the confection or sauce) is made by heating sugar to produce a brown, complex-flavored product. Caramel color is made by a controlled industrial process specifically designed to produce stable brown color, not caramel flavor. The Maillard reactions and sugar caramelization that create caramel flavor occur differently than the processes used to produce food-grade caramel color."

"How can I tell which class of caramel color is in my food?"

"You can't, from the label. US regulations only require 'caramel color' — not the class designation. Class I (used in some spirits) and Class IV (used in colas and many processed foods) are listed identically. The class matters for 4-MEI content. This is a genuine transparency gap."

"Did Coca-Cola change its recipe because of caramel color?"

"Coca-Cola and PepsiCo both reduced 4-MEI levels in their caramel color, specifically to avoid triggering Prop 65 labeling requirements in California. They stated the product tasted the same. This change happened around 2012 and applied to products sold nationally, not just in California."

"What is 4-MEI and why does it matter?"

"4-Methylimidazole (4-MEI) is a compound that forms as a byproduct when sugars react with ammonium compounds during the production of Class III and IV caramel colors. NTP rodent studies found it caused lung tumors in mice and rats at high doses. IARC classified it as Group 2B (possibly carcinogenic). The FDA calculated that human exposure is too low to constitute a meaningful risk."

Caramel Color: Four Types, One Controversy

Quick Answer

Caramel color is not one ingredient — it's four different ones (Classes I-IV). Classes I and II are not a concern. Classes III and IV are made with ammonium compounds and produce a byproduct called 4-methylimidazole (4-MEI). The NTP found 4-MEI caused lung tumors in rodents. IARC classified it as possibly carcinogenic. The FDA disagrees that human exposure warrants action. Major cola companies reduced 4-MEI after California's Prop 65 listed it.

The Science

If you’ve drunk a cola today, you’ve consumed caramel color. Probably Class IV caramel color, which is made with both sulfite and ammonium compounds and is the class at the center of a 4-methylimidazole (4-MEI) controversy that prompted California to act while the FDA declined to.

The story is worth understanding, because “caramel color” on a label tells you almost nothing about what you’re actually getting.

Not One Thing: The Four Classes

Caramel color (E150 in EU designation) is produced by heating food-grade carbohydrates under controlled conditions. What distinguishes the four classes is which reactants are used in that heating process.

Class I (E150a): plain caramel. Sugar is heated with acid or alkali only — no sulfite, no ammonium compounds. The result is a warm brown color with relatively little 4-MEI. Used primarily in spirits like whisky and brandy where ammonia-derived colors are prohibited by some category standards.

Class II (E150b): sulfite caramel. Made with sulfite compounds as a reactant. Used in specific spirits and some foods.

Class III (E150c): ammonia caramel. Made with ammonium compounds. The ammonia reacts with sugars to produce color — and also produces 4-MEI as a byproduct. Used in beer, soy sauce, some baked goods.

Class IV (E150d): sulfite ammonia caramel. Made with both sulfite and ammonium compounds. This is the most widely used class. It’s the brown in cola beverages, many dark baked goods, gravies, and countless processed foods. It has the highest 4-MEI content.

When a label says “caramel color,” you’re reading two words that conceal four chemically distinct possibilities. Most of the time, in most processed foods, you’re getting Class IV.

The 4-MEI Problem

4-Methylimidazole is an organic compound. It forms as a byproduct of the Maillard-like reactions between sugars and ammonium compounds during Class III and IV caramel color production. The amount present in the final colorant depends on production conditions, time, temperature, and manufacturer.

In 2007, the National Toxicology Program (NTP) conducted a two-year rodent study on 4-MEI. Mice and rats were given 4-MEI in drinking water at doses ranging from 312 to 2,500 ppm. The results: lung tumors in male and female mice at the higher dose groups, and some evidence of alveolar/bronchiolar tumors.

Based on these findings, IARC evaluated 4-MEI and classified it as Group 2B: “possibly carcinogenic to humans.” That’s the same category as aspartame and pickled vegetables — limited evidence, not established causation.

California’s Office of Environmental Health Hazard Assessment (OEHHA) listed 4-MEI under Prop 65 with a threshold of 29 micrograms per day. Products that might expose consumers to more than 29 micrograms per day would require a Prop 65 cancer warning.

What the FDA Said

The Center for Science in the Public Interest (CSPI) filed a petition in 2011 asking the FDA to prohibit Class III and IV caramel colors. The FDA declined.

The FDA’s position: typical human exposure to 4-MEI from caramel color is far below the doses that caused tumors in rodents. The FDA calculated that a consumer would need to drink more than 1,000 cans of cola per day to reach exposures comparable to those that caused effects in mice — a biologically absurd scenario.

The FDA also noted that rodent carcinogenicity studies at extreme doses don’t translate directly to human cancer risk, and that 4-MEI occurs naturally in many foods (roasted coffee, cooked meats, soy sauce) beyond just caramel color.

The Cola Company Response

Even though the FDA didn’t require action, Coca-Cola and PepsiCo reduced 4-MEI levels in their products around 2012. The motivation was California’s Prop 65: selling products in California that required a cancer warning would be costly and damaging to brand perception.

Both companies stated that the reformulated caramel color produced an equivalent taste in their beverages. They also stated, accurately, that the Prop 65 threshold is extremely conservative and doesn’t indicate that the original product was dangerous.

Consumer Reports tested products before and after the reformulation and found significant reductions in 4-MEI. The change was real.

How EFSA evaluated caramel colors vs the FDA approach

EFSA’s 2011 re-evaluation of caramel colors (E150 a-d) established acceptable daily intakes:

Class I: 200 mg/kg/day
Class II: no ADI specified (insufficient data for Class II specifically)
Class III: 150 mg/kg/day
Class IV: 150 mg/kg/day

EFSA also recommended that 4-MEI content in caramel colors be monitored and manufacturers work to reduce levels where possible. EFSA’s position was more cautious than the FDA’s: they didn’t say it was dangerous, but they wanted producers to minimize 4-MEI production.

This difference between the FDA and EFSA approaches to caramel color reflects a broader pattern: EFSA tends toward precautionary ADI-setting while the FDA tends to require demonstrated harm before imposing limits.

What This Means in Practice

If you eat a mostly whole-food diet, caramel color exposure is low and 4-MEI exposure from it is negligible.

If you drink several colas daily, eat processed soups, gravies, and dark baked goods regularly, caramel color is a significant part of your additive intake. Even then, the FDA’s analysis suggests the 4-MEI risk is theoretical rather than demonstrated in humans.

The caution verdict here is specific to Class III and IV. Class I caramel (in some spirits and premium products) is not a 4-MEI concern.

The transparency gap is the most legitimate frustration: you can’t identify which class you’re consuming from the label. That’s information manufacturers and regulators could provide but currently don’t.

What This Means for You

You can't tell which class of caramel color is in a product from the label — it just says 'caramel color.' Cola drinks, dark soy sauces, gravies, and dark baked goods are the most common sources of Class IV. If you're concerned, reducing processed foods overall reduces exposure to multiple additives at once, which is a more actionable approach than trying to avoid a single unlabeled class.