Hidden Allergens on Foreign Menus: A Traveller's Guide

If you have a serious food allergy, eating abroad is an exercise in trust. You can't read the menu, you can't easily ask the kitchen, and the language barrier means even careful explanations get lost.

This guide is about the allergens travellers most often miss — not the obvious ones, but the dishes that contain an allergen without naming it on the menu.

A serious note before we start. This is general traveller information. If you have a life-threatening allergy, always carry your auto-injector, always carry a translation card written by a medical professional in the local language, and always confirm with the kitchen before ordering. No app, including ours, replaces those steps.

Gluten — the sneakiest allergen abroad

Wheat and gluten hide in places they don't in English menus.

• Soy sauce — most Asian soy sauces contain wheat. Tamari is the gluten-free version, but it's rarely the default.
• Soba noodles — should be 100% buckwheat, but many Japanese restaurants use a buckwheat-wheat blend. Ask if it's jūwari (十割), meaning 100% buckwheat.
• Imitation crab (surimi) — used in California rolls, Caesar salads, and many seafood dishes. Almost always contains wheat starch.
• Roux-based sauces — French béchamel, velouté, espagnole are all flour-thickened. Béarnaise and hollandaise are usually gluten-free, but anything labelled sauce mère or sauce (without further qualification) is suspect.
• Beer batter in tempura outside Japan — many Western restaurants use beer in their tempura batter, even though traditional Japanese tempura doesn't.

Dairy — beyond the obvious

Dairy is hidden less often than gluten, but the surprises are similar.

• Pesto — most pestos contain Parmesan or pecorino. Always ask.
• Risotto — almost universally finished with butter and Parmesan, even when it doesn't say so.
• "Vegetarian" — in many countries this just means no meat. Cheese, butter, ghee, cream are all standard.
• Indian curries — many North Indian dishes are finished with cream, ghee, or yoghurt. Korma, butter chicken, paneer dishes are obvious; tikka masala and makhani are the giveaways for cream.
• Bread products in France — French pastries are usually butter-laden. Brioche, croissants, even some baguettes contain milk or butter.

Nuts — the most regional

Nut usage varies enormously by cuisine, and the risk follows.

• Pesto — pine nuts. Some restaurants substitute walnuts.
• Romesco (Spain) — almonds and hazelnuts.
• Mole sauces (Mexico) — usually contain nuts and seeds.
• Pad thai — peanuts, often as garnish but also in the sauce.
• Satay — peanut sauce, obvious. But peanut oil shows up in much wider Southeast Asian cooking.
• Baklava and Middle Eastern desserts — pistachios, walnuts, almonds, often together.
• Marzipan — almonds, common in European desserts.
• Cross-contamination in Asian kitchens is high. A wok used for one peanut dish is then used for the next dish without nuts.

Shellfish and fish — easy to miss when you weren't expecting them

• Caesar dressing — anchovies. Almost always.
• Worcestershire sauce — anchovies. Used in many marinades, Bloody Marys, and sauces.
• Thai and Vietnamese sauces — nam pla (fish sauce) is in roughly everything. Pad thai, green papaya salad, Vietnamese pho broth, all contain it.
• Bottarga (Italy) — cured fish roe, sometimes shaved over pasta or eggs without much warning.
• Bouillabaisse — fish stew, but it's the broth in many "vegetable" sides in Provence too.
• Surimi — see gluten section above.

Egg — the one most people forget about

• Fresh pasta is made with egg. Dry pasta usually isn't, but in Italy a tagliatelle or fettuccine labelled "all'uovo" is egg-rich.
• Mayonnaise, aioli, carbonara, hollandaise, béarnaise, caesar dressing — all egg.
• Marshmallows — often contain egg white.
• Most pastries — croissants, brioche, cakes.
• Asian noodles — many ramen and udon noodles contain egg. Most Chinese noodles do.

Sesame — the rising allergen

Sesame is increasingly common as a serious allergen and often missed:

• Hummus and Middle Eastern dips (tahini)
• Burger buns — visible seeds, but also baked in
• Asian dressings and sauces — sesame oil is everywhere in Korean, Chinese, Japanese cooking
• Halva — sesame-based dessert

How to communicate it

A few practical rules that work across countries:

1. Carry an allergen card in the local language. Get it written or checked by a native speaker, not Google Translate. Print multiple copies.
2. Tell the waiter at ordering time, not when the food arrives. Many kitchens can adapt with notice; few can swap a finished dish.
3. Be specific. "I am allergic to peanuts" is clearer than "I have a nut allergy" — peanuts are botanically a legume, and the distinction matters in some kitchens.
4. Confirm with the kitchen, not just the waiter. In some countries the waiter relays orders without checking. Politely ask them to confirm with the chef.
5. Avoid buffets and shared-utensil situations. Cross-contamination risk is high.

How a menu translator helps

Most translation apps don't surface allergen information at all — they just translate dish names. Menufy automatically flags common allergens (gluten, dairy, nuts, shellfish, fish, egg, sesame) when ingredients suggest them, so you can scan a menu and immediately see which dishes need a closer look.

It's not a substitute for telling the kitchen. But it's a faster filter — instead of reading every dish description hoping to spot a risk, you see flags at a glance.

Get Menufy free before your next trip. And whatever app you use — please, carry that allergen card.