Lysozyme

Case notes

Lysozyme reads like something from a chemistry syllabus, not a breakfast food. Nothing in the word points to egg, and there's no familiar root to catch your eye the way "albumin" or "ovomucoid" might for a parent who has been reading egg labels for a while. It belongs to the Ovomucoids family, the group associated with egg allergy, and it can also appear as egg lysozyme or simply as E1105 — a code with no words in it at all.

The other reason it slips by is context. Lysozyme is used as a preservative in some cheeses and wines, which are not the products most people are scanning for hidden egg. A label check often speeds up once a food feels categorically unrelated to the allergen in question, and that's exactly where a short additive name at the end of an ingredient list tends to go unread.

It's worth adding all three forms — lysozyme, egg lysozyme, and E1105 — to whatever list you carry or share with caregivers, alongside the egg names you already watch for. The family's dominant egg white protein, ovomucoid (Gal d 1), is heat-stable, so cooking or processing isn't a reliable clue that the ingredient has changed character. Reactions in this family can include anaphylaxis, which is reason enough to treat an unfamiliar additive name as something to look up rather than skim past. If a product's ingredient list is unclear, the manufacturer is the fastest route to a definite answer.