What is E321?

Butylated hydroxytoluene (BHT), also known as dibutylhydroxytoluene, is a lipophilic organic compound, chemically a derivative of phenol, that is useful for its antioxidant properties and is widely used as a food preservative in different parts of the world. BHT is widely used to prevent free radical-mediated oxidation in fluids and other materials, and the regulations overseen by the US FDA—which considers BHT to be "generally recognized as safe"—allow small amounts to be added to foods. E321 sits in the E300–E399 series, which in the EU classification mainly covers antioxidants and acidity regulators.

What is E321 used for?

E321 belongs to the antioxidants group. Antioxidants stop fats going rancid and food discolouring. Several are natural, such as ascorbic acid (vitamin C).

Is E321 safe?

E321 is rated “moderate”. It is approved for use in food, but some people prefer to limit it. “Moderate” means it is approved, but is debated or something some people prefer to limit.

How E321 appears on labels

On food packaging you'll find E321 either as the number “E321” or by the name “BHT (Butylated hydroxytoluene)” in the ingredient list, often after its function. Ingredients are listed in descending order by weight, so an additive near the end is present only in small amounts.

Is E321 vegan?

Yes, E321 is suitable for vegans.