Mustard allergy

A mustard allergy is a reaction of the immune system to proteins in mustard seeds. It covers whole and ground seeds, mustard powder, prepared mustard and mustard oil. Reactions can be severe. In the EU and the UK mustard is one of the 14 allergens, so it is easy to spot on European labels and harder to spot elsewhere.

Substitutes

• To hold a dressing together: honey, a little miso, or a spoon of yogurt if those are safe for you. Whisk the oil in slowly to help it emulsify.
• For tang: a little extra vinegar or lemon juice.
• For heat: a pinch of chili flakes or black pepper.

Horseradish and wasabi come from the same plant family as mustard, and some people with a mustard allergy react to them, or to related vegetables. Ask your doctor or a dietitian which swaps are safe for you.

Common mistakes

• Missing mustard in vinaigrette, mayonnaise, rémoulade and many salad dressings.
• Forgetting mustard seed in pickles, relishes, chutneys and pickling spice.
• Missing it in curry powders and Indian spice mixes, sausages, marinades, barbecue sauces and some ketchups.
• Expecting a US label to warn you. Mustard is not one of the US major allergens. It is listed by name when it is an ingredient, but mustard seed can be covered by the word "spices".
• Cooking with mustard oil without realizing it. It is common in Bengali, Punjabi and other South Asian cooking.

In recipes

Mustard is often a background ingredient rather than the main flavor. A spoon of mustard helps oil and vinegar stay mixed, adds sharpness to sauces and glazes, and goes into rubs for meat. Whole mustard seeds are fried in hot oil at the start of many Indian dishes. In the EU and the UK, prepacked food must emphasize mustard in the ingredients list, and restaurants must be able to tell you if a dish contains it.

If you have a mustard allergy, read the label every time you buy sauces, dressings and spice mixes, ask in restaurants, and talk to a doctor about a plan for eating out.