Hidden allergens in food labels: 12 you might miss
Allergens don’t always appear on a label under their everyday name. Some hide behind technical terms, additive codes, or ingredient derivatives that look harmless if you don’t know what they are.
This is a list of common hiding spots — the kind of thing an AI ingredient scanner will flag automatically, but worth knowing manually too.
Why hidden allergens exist
Food manufacturers use technical names for two reasons. Some are genuine industrial ingredients with their own names (lecithin, casein, albumin). Others are derivatives — refined or modified versions of an allergen — that don’t always get labelled the way you’d expect.
In the UK and EU, the 14 major allergens must be emphasised on the label, usually in bold. But the emphasis doesn’t always make it obvious which technical term refers to which allergen. That’s where the confusion creeps in.
12 hidden allergens to know
1. Lecithin → usually soy
Lecithin (also written E322) is an emulsifier used in chocolate, baked goods, margarine, and a huge range of processed foods. The vast majority of commercial lecithin is soy-derived. Sunflower lecithin exists but is less common and usually labelled explicitly.
If you have a soy allergy and see “lecithin” without a source, treat it as soy until proven otherwise.
2. Casein and caseinate → milk
Casein is the main protein in milk. Calcium caseinate and sodium caseinate show up in non-dairy creamers, processed cheeses, protein bars, and even some “lactose-free” products. They are milk and are not safe for a milk allergy.
3. Whey, lactose, lactalbumin → milk
All milk-derived. Whey protein in particular hides in protein bars, baked goods, and processed meats.
4. Albumin / albumen → egg
Egg white is mostly albumen. Egg albumin appears in some baked goods, meringues, and protein powders. Bovine albumin is a different thing (from cow blood, used in some pharmaceuticals) — but in food, “albumin” almost always means egg.
5. Hydrolysed vegetable protein (HVP) → often soy or wheat
HVP is a flavour enhancer made by breaking down plant proteins. Common sources are soy and wheat, both major allergens. If the label doesn’t specify, you can’t assume it’s safe.
6. Modified food starch → can be wheat
In the EU, “modified starch” without a source is usually corn or potato. In the US and elsewhere, wheat is a common source. Always check the country of origin and the allergen emphasis.
7. Semolina, durum, kamut, spelt, triticale → wheat
All forms of wheat. Semolina is used in pasta and couscous; durum is a hard wheat used in pasta flour; spelt and kamut are ancient wheat varieties marketed as “alternatives” but still contain gluten and trigger wheat allergies.
8. Couscous, bulgur, farro, freekeh → wheat
Whole-grain or pre-cooked wheat products. Often shelved under “ancient grains” or “Mediterranean” but they’re all wheat.
9. Surimi → fish + sometimes shellfish
Surimi is processed white fish (often pollock) reformed into crab-stick or seafood-stick shapes. Some brands flavour it with crab or shrimp extract. A fish allergy rules surimi out; a shellfish allergy may also rule it out depending on the flavouring.
10. Worcestershire sauce → fish (anchovies)
Anchovies are a core ingredient of traditional Worcestershire sauce. Hidden in Caesar dressing, marinades, and “umami” sauces.
11. Carmine / cochineal / E120 → insect-derived
Carmine (also carminic acid, cochineal, E120) is a red food colouring made from crushed cochineal insects. Not an allergen in the usual sense, but worth knowing if you avoid insect-derived products for ethical or religious reasons, or if you’ve had reactions to it.
12. Natural flavourings → can hide allergens
“Natural flavourings” is a catch-all that can include milk, soy, or wheat derivatives without being explicitly listed in some jurisdictions. In the UK and EU, the 14 major allergens must still be flagged separately even when used as flavourings. Outside the UK/EU, less so. For severe allergies on imported products, this is a real risk.
Why an AI scanner helps
Reading every ingredient on every package is exhausting. An AI allergen scanner does the boring work — recognising “lecithin” as a soy risk, “caseinate” as a milk risk, “modified starch” as worth checking — and flags them in seconds.
That doesn’t replace careful label-reading for severe allergies. It catches what you’d otherwise miss when you’re tired, distracted, or shopping in a foreign language.
What about additives and E-numbers?
Many allergens are also packaged into E-numbered additives. Soy lecithin (E322), egg lysozyme (E1105), and sulphites (E220–E228) are common culprits. We maintain a full E-number directory with risk information for each, so you can look up anything you see on a label.
The TL;DR list
If you only want one thing to remember:
| Hidden name | Real allergen |
|---|---|
| Lecithin / E322 | Soy (usually) |
| Casein, caseinate, whey, lactalbumin | Milk |
| Albumin, albumen | Egg |
| Hydrolysed vegetable protein | Soy or wheat |
| Modified starch (US-origin) | Wheat (often) |
| Semolina, durum, spelt, kamut, bulgur, farro, freekeh | Wheat |
| Surimi | Fish, sometimes shellfish |
| Worcestershire sauce | Fish (anchovies) |
| Carmine / E120 | Insect (cochineal) |
| Natural flavourings | Variable — check label |
When in doubt, scan it. When still in doubt, check the allergen emphasis or call the manufacturer.
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