The short answer
Besides the 9 major allergens, U.S. rules require a handful of ingredients to be declared in a specific way. Generic EU or Asian wording — “colour”, “E220”, “sweetener”, “flavour enhancer” — is a common reason for label problems at the border.
| Ingredient | What the U.S. label must do | Rule |
|---|---|---|
| Sulfites | Declare by name if 10 ppm or more is in the finished food — even if the sulfite came in with an ingredient | 21 CFR 101.100(a)(4) |
| Certified colors | Declare by name, for example “FD&C Yellow No. 5” or “Yellow 5”; lakes as “Blue 1 Lake” | 21 CFR 101.22(k)(1) |
| Cochineal extract / carmine | Declare as “cochineal extract” or “carmine” — not “color added” | 21 CFR 73.100(d)(2), since January 5, 2011 |
| Aspartame | “PHENYLKETONURICS: CONTAINS PHENYLALANINE” on the principal display panel or information panel, prominent | 21 CFR 172.804(d)(2) |
| Sorbitol | “Excess consumption may have a laxative effect” if foreseeable use could reach 50 g a day | 21 CFR 184.1835(e) |
| Monosodium glutamate | Declare as “monosodium glutamate” | 21 CFR 101.22(h)(5) |
| Protein hydrolysates | Declare by specific name (for example “hydrolyzed soy protein”) — not just “flavor” | 21 CFR 101.22(h)(7) |
1. Sulfites
Sulfiting agents include sulfur dioxide, sodium sulfite, sodium bisulfite, potassium bisulfite, sodium metabisulfite and potassium metabisulfite. Normally an additive carried in by an ingredient with no effect in the final food need not be listed — but for sulfites that exemption applies only if no detectable amount remains, and 10 ppm or more counts as detectable.
- Common sources: dried fruit, wine or vinegar used as an ingredient, shrimp, dehydrated potatoes and vegetables, fruit fillings, some spice blends.
- FDA Import Alert 99-21 allows detention without physical examination of imported foods with undeclared sulfites. See dried fruit exporters.
- Use the name, not an E-number: “sodium metabisulfite (preservative)”, not “E223”.
2. Colors
The seven FDA-certified food colors must be declared by name — “FD&C” and “No.” may be dropped, so “Red 40” and “Yellow 6” are fine. Colors exempt from certification (such as paprika extract or annatto) may be declared as “artificial color”, “color added” or by name — except cochineal extract and carmine, which must always be named. Check that every color is permitted in U.S. food at all; see the Red No. 3 ban.
3. Sweeteners
- Aspartame needs the phenylketonurics statement in bold, set off from other text.
- Sorbitol needs the laxative statement where daily intake could reach 50 g — common in sugar-free candy and gum.
- Sweeteners must be named in the ingredient list — “sweetener (E951)” is not a U.S. declaration.
4. Flavor enhancers
MSG must be called “monosodium glutamate”. Protein hydrolysates used for flavor must be named by source, such as “hydrolyzed wheat protein” — which also helps with the wheat or soy allergen declaration.
Example: a snack maker in Türkiye and a sauce maker in Thailand
A Turkish dried apricot snack uses fruit treated with sulfur dioxide, and tests show 400 ppm in the finished product. The U.S. label reads “dried apricots, sulfur dioxide (to preserve color)”. A Thai chili sauce maker replaces “colour (E124), flavour enhancer (E621)” with a U.S.-permitted color named on the label and “monosodium glutamate”, because E124 is not a color FDA permits in food.
Basic food label review (ingredient list, allergens, net quantity) $250. Standard review with Nutrition Facts $550. Advanced review with claims $750.
Frequently asked questions
When must sulfites be declared on a US food label?
When the finished food contains 10 ppm or more of sulfites, even if they came in through an ingredient.
Can I write E-numbers on a US label?
No. U.S. ingredient lists use common or usual names, such as “sodium metabisulfite” or “Yellow 5”.
Can I declare carmine as “natural color”?
No. It must be declared as “cochineal extract” or “carmine”.
Where does the aspartame warning go?
On the principal display panel or the information panel, prominently, reading “PHENYLKETONURICS: CONTAINS PHENYLALANINE”.
Sources
- 21 CFR 101.100 — Food labeling exemptions (sulfites, 10 ppm)
- 21 CFR 101.22 — Colors, MSG and protein hydrolysates
- FDA — Declaring cochineal extract and carmine by name
- 21 CFR 172.804 — Aspartame
- 21 CFR 184.1835 — Sorbitol
Rules checked on November 11, 2026. This article is general information, not legal advice.