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🦐 Crustacean Shellfish allergy: label names, hidden sources & scanning
Crustacean shellfish (shrimp, crab, lobster, crayfish) are among the most frequent causes of severe food reactions in adults. Cross-contact in kitchens and shared fryers is a common risk even when no shellfish is listed.
Hidden label names our scanner matches
An ingredient list can contain crustacean shellfish without ever using the word. These are the actual terms Scallergy's matching engine checks — the same list the app uses when it scans a barcode:
Common derivatives
Where crustacean shellfish commonly hides
- seafood mixes and paella
- shrimp paste in Asian sauces
- bisques and seafood stocks
- surimi blends
- fried foods from shared fryers
- some fish feeds/flavourings
How Scallergy verdicts crustacean shellfish
Avoid — crustacean shellfish (or one of the label names above) appears in the product's ingredient list.
Caution — the product carries a “may contain” / cross-contamination warning for it.
Unknown — we don't have trustworthy ingredient data, and we say so instead of guessing. The verdict is always driven by what's in the product; the severity you set in your profile is shown as context.
Scan for crustacean shellfish in seconds
Set crustacean shellfish in your allergen profile once — every barcode scan checks all 12+ label names above automatically. Free, independent, no ads.
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Frequently asked questions
Which label names mean crustacean shellfish?
Beyond the word “crustacean shellfish” itself, look for terms like crab, lobster, shrimp, prawn, prawns, crayfish. These are the exact terms Scallergy's scanner matches when it checks an ingredient list.
Does crustacean shellfish have to be declared on the label?
Yes — in the EU (Regulation 1169/2011, Annex II) and the US (FALCPA/FASTER Act) crustacean shellfish must be emphasised in the ingredient list of prepacked food.
What does “may contain crustacean shellfish” mean?
“May contain” is a voluntary cross-contamination warning: the product doesn't list it as an ingredient, but it is made where contact is possible. Scallergy shows these as a Caution verdict — distinct from Avoid, which means the allergen is actually in the ingredient list.
Can Scallergy guarantee a product is crustacean shellfish-free?
No — no app can. Scallergy checks ingredient data from USDA FoodData Central, Open Food Facts, and community submissions, shows its source and an honest “Unknown” when data is thin, and is assistive only: always check the printed label and follow your allergist's advice.
Related allergens
Scallergy is assistive, not medical advice. Ingredient data can be incomplete or out of date — always check the physical label and consult an allergist about your allergies. Sources: EU Regulation 1169/2011 (Annex II); US FALCPA (2004) and FASTER Act (2021); our data sources.