Tahini

Cross-reactivity

Case notes

Tahini is sesame, but the word sesame does not appear anywhere in it. That single gap is what makes it one of the easier sesame-derived ingredients to read straight past. It also travels under other names — sesame paste, sesame butter, and tahina — and only two of those four spell the allergen out. On a crowded ingredient panel, "tahini" can look like a flavoring or a texture agent rather than a declared seed ingredient.

The most common place this shows up is hummus, which almost always contains tahini and is one of the most frequent routes to accidental sesame exposure. Because hummus is often served as a snack, a dip, or a sandwich spread rather than a packaged item with a panel to read, there may be no label to check at all. Sesame under the tahini name also appears in related products worth knowing by sight, including halvah and gomasio.

Tahini's proteins sit in the 2S albumins family, a group of seed storage proteins that also includes allergens from peanut, walnut, cashew, and hazelnut. Cross-reactivity within that family varies: the SleuthIt dataset notes that roughly 25 to 50 percent of people allergic to peanut react to tree nuts, that cashew-pistachio cross-reactivity is very strong, and that peanut-hazelnut cross-reactivity is variable. Reactions in this family can range from contact dermatitis to respiratory symptoms and, in severe cases, anaphylaxis. Any decision about what that means for one child belongs with their clinician.