Potassium bromate

Potassium bromate strengthens dough. It lets a flour rise higher and hold its shape, and it is used up during baking, which is the argument that has kept it legal in the United States while most of the world removed it.

The regulatory route it takes is unusual and worth following, because it explains why the ingredient is hard to find on a label.

Two regulations, and only one of them is the one you want

Search the US food additive regulations for potassium bromate and you land on a section that permits it “in the malting of barley”, for use in “fermented malt beverages or distilled spirits”, at up to 75 parts per million in the malt.

That is beer and spirits. It is not bread, and a reader who stops there will conclude the bread use is unapproved.

The bread use comes from somewhere else entirely: a standard of identity. Bromated flour is a defined food, and its definition permits potassium bromate “in a quantity not exceeding 50 parts to each million parts of the finished bromated flour”, added “only to flours whose baking qualities are improved by such addition”.

So the permission is a definition of what a flour is, rather than an approval of an additive. That distinction is invisible to a reader and it is the reason the answer to “is this approved” depends on which book you open.

Where it stands now

Most of the world removed it. The United Kingdom, the European Union, Canada, Brazil, China and others prohibited it from bread, largely from the 1990s onwards, following animal carcinogenicity findings.

California legislated. The California Food Safety Act provides that from 1 January 2027 no person or entity shall manufacture, sell, deliver, distribute, hold or offer for sale in commerce a food product for human consumption containing potassium bromate, alongside brominated vegetable oil, propylparaben and Red dye 3. Penalties run to $5,000 for a first violation and $10,000 for each subsequent one.

Federal rules are unchanged. Bromated flour remains a lawful standardised food.

This is one of the genuine cases in the cluster on ingredients banned somewhere else, and it runs in the less familiar direction: here it is the American position that is the outlier rather than the cautious one.

What the argument turns on

The industry case is that bromate is consumed during baking, converting to bromide, so a correctly baked loaf contains little or none.

The objection is that this depends on the baking being right. Under-baking, too much bromate, or a formulation that does not use it up all leave residue, and the reader has no way to know which loaf they are holding. A safety argument that rests on the process being performed correctly is a different kind of argument from one that rests on the substance being harmless.

Finding it on a label

Look for “bromated flour” or “enriched bromated flour” in the ingredient list rather than for potassium bromate itself. That is the form the standard of identity produces, and it is the reason the chemical name often does not appear.

Bakers who have moved away from it usually say so, because it is a selling point. Where they have not, Azodicarbonamide and L-Cysteine are the two dough conditioners you are most likely to meet instead, and each has its own file.