INS 321 / E321AntioxidantVegan

BHT (Butylated Hydroxytoluene) (INS 321)

TL;DR

INS 321 is BHT, short for butylated hydroxytoluene. It is a synthetic antioxidant used to keep fats, oils, and dry mixes from going rancid, often paired with BHA (INS 320) for stronger protection. It is generally vegan and is permitted by FSSAI for specified food categories with restrictions.

Quick Facts

INS Number
321
E-Number
E321
Category
Antioxidant
Veg Status
Vegan
FSSAI Status
Permitted with restrictions
JECFA ADI
0-0.3 mg/kg bw (1995)
Chemical Name
2,6-di-tert-butyl-4-methylphenol

What is INS 321?

INS 321 is BHT, short for butylated hydroxytoluene. It is a synthetic antioxidant used to keep fats, oils, and dry mixes from going rancid, often paired with BHA (INS 320) for stronger protection.

Why brands add it

Brands use it because it works at very low concentrations and stays stable through baking and frying. It is common in oily snacks, packaged baked goods, and anything with a long shelf life that contains fat.

Where you'll find it

INS 321 commonly shows up on Indian packets in these categories:

  • fried snacks and namkeen
  • biscuits and bakery
  • chewing gum
  • instant soup and gravy mixes
  • vegetable oils and shortenings
  • breakfast cereals

Veg or non-veg? - Vegan

BHT is produced by chemical synthesis from p-cresol and isobutylene. No animal product is used in its manufacture.

FSSAI status and JECFA evaluation

FSSAI: Permitted by FSSAI as an antioxidant under Schedule I of the FSS (Food Products Standards and Food Additives) Regulations 2011 for specified food categories, with category-specific upper limits often expressed as a combined synthetic-antioxidant maximum.

JECFA: ADI 0-0.3 mg/kg body weight established at the 44th JECFA (1995), based on effects in 2-generation rat reproduction studies and hepatic enzyme induction. EFSA's 2012 re-evaluation set a similar ADI of 0.25 mg/kg bw based on a thresholded mode of action.

Also known as

On packets, in recipes, and in conversation, INS 321 is also called:

321ins 321e321e 321bhtbutylated hydroxytoluene2,6-di-tert-butyl-p-cresoldibutylhydroxytoluene

Frequently Asked Questions

Is INS 321 vegetarian?+
Vegan. BHT is produced by chemical synthesis from p-cresol and isobutylene. No animal product is used in its manufacture.
Is INS 321 permitted by FSSAI?+
Permitted by FSSAI as an antioxidant under Schedule I of the FSS (Food Products Standards and Food Additives) Regulations 2011 for specified food categories, with category-specific upper limits often expressed as a combined synthetic-antioxidant maximum.
What is INS 321 used for?+
Brands use it because it works at very low concentrations and stays stable through baking and frying. It is common in oily snacks, packaged baked goods, and anything with a long shelf life that contains fat.
Is INS 321 (also written as E321) the same thing?+
Yes. INS 321 (the Codex International Numbering System used by FSSAI) and E321 (the European E-number system) refer to the same compound. The digits are identical for almost all common additives. Indian packets may show either form, or the common name (bht (butylated hydroxytoluene)).

Sources

Last verified: 2026-04-29.

Regulatory status, not medical advice
This page summarises FSSAI's permission status and JECFA's scientific evaluation. It is not medical or dietary advice. Manufacturer ingredient sourcing can vary, especially for source-dependent additives - the Indian veg/non-veg dot logo on the pack is the brand's declaration. For health decisions, consult a doctor or registered dietitian.

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