Croissant

A croissant is wheat flour laminated with butter, and the lamination depends on gluten - it is the protein network that holds the layers apart as they rise. There is no version of the technique without it.

A croissant is mostly butter and air by volume, so the flour weight is lower than its size suggests - and butter carries no FODMAP worth counting. One small croissant is often manageable; the pain au raisin next to it is not, because the raisins bring their own load. This food is not among the 55 grain products behind this axis's per-portion figures, so its level is a placing and not a measurement.

Croissant: same reason as the FODMAP level: wheat fructans, in a pastry that is mostly butter and air by volume. Fat carries no chains, so the flour weight is what counts and it is lower than the size suggests.

A croissant does not hide its dairy - it is made of it. Butter is most of the recipe by reputation, but butter is nearly all fat and carries very little lactose; the milk in the dough is where the sugar actually is.

Croissant is low because it is a short-risen dough, baked before anything accumulates. Baking and drying are the two processes that end the amine question rather than starting it - heat kills the bacteria and dryness stops the rest. A sourdough proved for two days is the counter-example.

A croissant carries sugar in the dough, but far less than a pastry - the richness comes from butter, not from sweetening. A pain au chocolat is a different answer.

A croissant is refined flour and butter. Both are low, and the butter is genuinely empty - fat carries almost no metal at all.

A croissant is refined wheat flour and butter - the milling took the bran and germ, and the lamination adds fat, not plant fibre. The oxalate a wholemeal loaf would carry is simply not in the dough.