Sesame

What a sesame allergy is

A sesame allergy is a reaction to proteins in the seed of Sesamum indicum. Sesame is not a nut, not a legume and not related to any other major allergen, so it sits on its own — which is why it took so long to be regulated alongside the others, and why an allergen list from ten years ago may not mention it.

Two things make sesame awkward to avoid. The first is that the seeds are small, loose and mobile: they scatter off buns, sit in the bottom of bread baskets and fryer baskets. The second is that sesame is one of the most widely travelled ingredients in the world’s kitchens — Middle Eastern, North African, Indian, Chinese, Japanese, Korean and West African cooking all use it heavily — and each of those traditions has its own word for it.

The names that do not say “sesame”

Tahini, also written tahina or tahin, is ground sesame paste. It is the base of hummus, of baba ganoush, and of the sauce on most falafel and shawarma. Where a label lists hummus as a component, sesame is very likely present, because almost all recipes use tahini.

Halvah is a sweet confection; the Middle Eastern and Balkan versions are made from tahini, though the word also describes semolina-based sweets in South Asia, so it is a strong hint rather than a certainty.

Za’atar is a herb and spice blend that conventionally includes toasted sesame seeds, and dukkah is an Egyptian nut and seed mix built around them. Gomashio — Japanese gomasio — is sesame and salt, sprinkled on rice.

Benne and benniseed are the words used in the American South and much of West Africa. Gingelly, jinjili and gingelly oil are Indian English terms; til is the Hindi, Urdu and Bengali name; sim sim or simsim is the East African name.

Sesamol and sesamolin are compounds derived from sesame oil and used as antioxidants. Sesame flour is milled seed, used as a protein and texture additive — and, increasingly, as a deliberate cross-contact management strategy.

“Natural flavour” and “spices” deserve their own line. Before 2023, US labels could legitimately bury sesame inside either term, so any packaged food formulated before then, and any product outside FDA jurisdiction, may still be doing so.

How the label is worded where you are

The United States changed in 2023. The FASTER Act added sesame as the ninth major food allergen, in force from 1 January 2023, so FDA-regulated packaged food must now name sesame in plain English in the ingredient list or in a “Contains” line. Before that, sesame had no such protection and could hide inside collective terms.

The EU and UK have required sesame to be emphasised in the ingredient list for far longer — it has been on the Annex II list of allergens throughout, alongside milk, egg and the nuts, with no named exemptions for any sesame-derived ingredient. Elsewhere the seed may simply be listed among the others, in the local language, with no emphasis and no summary line.

Cross-contamination and “may contain”

Sesame produced the strangest side effect of any allergen rule. When the FASTER Act took effect, several large US bakeries concluded that keeping sesame out of their non-sesame lines was harder and costlier than putting a little in, so they began adding sesame flour to buns, breads and rolls and declaring it. That is lawful, and the label tells the truth. It also means that products which were reliably sesame-free before 2023 may not be now, and that reading the current label matters more than remembering a brand.

Precautionary wording — “may contain sesame seeds”, “made on a line that also handles sesame” — remains voluntary and unstandardised in most places, with no legal ranking between phrasings, and its absence is not evidence that no sesame came near. Bakery counters, bread baskets, salad bars and shared fryers carry no ingredient list at all. PNut reports any such wording as May contain rather than resolving it one way or the other; what “may contain traces” actually means sets out what those lines do and do not tell you.

Reading a sesame label abroad

The European words are close to the English — sésamo, sésame, Sesam, sesamo — with Spanish ajonjolí as the exception worth memorising, since it is the ordinary word across much of Latin America. Outside Europe the script changes: 芝麻 on Chinese labels, تِل and تिल on South Asian ones, سمسم in Arabic. And the paste is often listed instead of the seed, so tahin, طحينة and tahini are as much worth recognising as the seed word itself. The table below gives both for each language, and reading a label in a language you don’t speak covers reading the list they sit in.

How PNut flags sesame

Scan the barcode and PNut looks the product up and reads its published ingredient list; photograph the ingredient panel instead and it reads the text off the label, in any of 40+ languages. It checks for sesame and for every regional name, paste and derivative on this page, then returns one of four verdicts — Safe, Contains allergen, May contain, or Unknown when the label cannot be read. It says Unknown rather than guessing.