Allergens that must be on the label
Manufacturers are required to disclose certain allergens at all times—even when their proportion is negligible and even when they entered the product as part of another ingredient. This is the strictest requirement in all of labeling: while a regular ingredient may be omitted if its proportion is small, an allergen may not.
What the regulations require
Technical Regulation TR CU 022/2011 lists components that can cause allergic reactions or are contraindicated for certain medical conditions, and requires them to be declared in the ingredients list regardless of their quantity.
The key phrase here is "regardless of quantity." A standard ingredient that makes up less than two percent of a compound ingredient may not need to be disclosed; an allergen must always be disclosed.
The list and the names under which they appear
| Allergen | How it may be listed |
|---|---|
| Peanuts and products thereof | peanut oil, peanut butter |
| Tree nuts and products thereof | almonds, hazelnuts, cashews, pistachios, pecans, macadamia nuts, Brazil nuts |
| Milk and products thereof | casein, caseinate, whey, lactose, milk powder |
| Eggs and products thereof | egg powder, albumin, lysozyme, melange |
| Fish and products thereof | fish oil, fish gelatin, fish sauce |
| Crustaceans and products thereof | shrimp, crab, crab extract |
| Mollusks | oysters, mussels, squid |
| Cereals containing gluten | wheat, rye, barley, oats, malt, semolina |
| Soy and products thereof | soy lecithin, soy protein, soy sauce |
| Sesame and products thereof | tahini, sesame oil |
| Mustard and products thereof | mustard powder, mustard oil |
| Celery and products thereof | celery salt, celery extract |
| Lupin and products thereof | lupin flour |
| Sulfur dioxide and sulfites | E220–E228, "preservative", indicated if content is above the threshold |
The right column is more important here than the left. A person who knows they have a milk allergy looks for the word "milk" in the ingredients list—and misses sodium caseinate or dry whey, which contain the same protein.
Sulfites are a special case
Sulfur dioxide and sulfites are the only items on the list where disclosure is tied to a threshold: they are indicated only if the content is above a set value, not always. The reason is that this is an additive rather than a food product, and small amounts are found everywhere—primarily in dried fruits, wine, and potato-based convenience foods.
The reaction to them is often not an allergy in the strict sense, but rather bronchospasm in people with asthma. This is the part of the list that covers not allergies, but "contraindicated for certain medical conditions."
What is not on the list
The list is closed, and it is important to understand this. It does not include the most common childhood allergens like red berries, citrus fruits, meat, or tomatoes. Reactions to these do occur, but mandatory disclosure is not required for them because the prevalence and severity of the reactions are lower.
The practical consequence: a person with an allergy not on the list must read the entire ingredients list rather than looking for a highlighted line.
How it looks on the packaging
The regulations do not prescribe a single way to highlight allergens, so in reality, three options are encountered:
- A separate line below the ingredients: "Contains: milk, wheat."
- Highlighting within the ingredients: the allergen is in bold or uppercase.
- No highlighting: the allergen is simply listed alongside the others—formally, this is sufficient.
The third option is the most common and the most inconvenient, and it is precisely because of this that one has to read the entire list. The order of reading is discussed in the article on reading ingredients.
A note on "may contain traces"
This label follows different rules: it is not about the ingredients, but about the production process, and it is voluntary. What lies behind it and when it should be taken seriously is covered in the article on traces of allergens.
A complete guide to each allergen and its names in ingredients is collected separately in the allergen reference guide.
When the label is no longer important
Reading the ingredients is about preventing a reaction. If one has already occurred, a different rule applies: in case of difficulty breathing, swelling of the face, lips, or throat, hoarseness, spreading rash, sudden weakness, or dizziness, emergency help is needed, not an analysis of the packaging.
For a person who has had such episodes before, a doctor prescribes self-administered medication, and having it on hand means more than any label reading. Diagnosing an allergy and determining exactly what to exclude and how strictly is also the doctor's domain: both missed allergies and unnecessary food exclusions have their costs.
Frequently asked questions
- Which allergens must be declared in the ingredients list?
- Peanuts, tree nuts, milk, eggs, fish, crustaceans, mollusks, cereals containing gluten, soy, sesame, mustard, celery, lupin and their derivatives, as well as sulfur dioxide and sulfites. This requirement is established by the technical regulation TR CU 022/2011.
- Can an allergen be omitted due to a small quantity?
- No. While a standard ingredient may not need to be disclosed if it makes up a small portion of a compound ingredient, an allergen from the list must be declared regardless of the amount. The exception is sulfites, for which disclosure is tied to a concentration threshold.
- Why don't I see the word "milk" even though I have an allergy to it?
- Milk protein can be listed under other names: casein, caseinate, whey powder, whey protein, lactose, or dried milk. You need to look for the entire group of names, not just one word.
- Are allergens required to be highlighted in bold?
- The regulation does not prescribe a single method for highlighting. You may encounter a separate "Contains" line, bolding within the ingredients list, or no highlighting at all—the latter is formally permissible, which is why you must read the entire ingredients list.
- What should I do if I am allergic to a product not on the list?
- Read the entire ingredients list rather than looking for a highlighted line. Mandatory disclosure is only established for the listed items; citrus fruits, berries, tomatoes, and meat are not included.
Read next
- "May contain traces": what is behind this label — The label "may contain traces of nuts" is found on half the shelves, including products where nuts have no business being.
- Allergy or intolerance: what is the difference and why it matters — Both conditions are described with the same words: "this makes me feel bad.
- How to read the ingredients list on a label: the rules governing its writing — A label looks like a list of words from which everyone reads something different: one person considers a long list of ingredients a red flag, another looks for E numbers.
This article is for general information. It is not medical advice, a diagnosis, or a prescription for treatment or a diet, and it does not replace a consultation with your doctor. If you have a health condition, are pregnant, take medication, or follow a diet prescribed to you, decisions about food belong with your doctor.
Figures from regulations, guidelines and studies are given as they stood when this article was prepared and may since have changed; check them against the primary sources. This article is not advertising, an offer, or individual advice, and neither the author nor the site owner is responsible for decisions taken on the basis of it.