E319 - Tertiary-butylhydroquinone (tbhq)

At a glance

• What it is: A food-grade antioxidant that protects fats and oils from oxidation
• Also called: TBHQ; E319; tert-butylhydroquinone
• What it does: Helps keep flavors and colors stable; delays rancid off-notes
• Where it’s used: Foods that contain added fats and oils
• Typical levels: Very small amounts, often up to 0.02% of the fat or oil content
• Source: Made synthetically (not naturally extracted)

Why is Tertiary-butylhydroquinone (tbhq) added to food?

TBHQ is added to slow oxidation in fats and oils, which prevents rancidity and keeps flavors and colors stable during storage and transport. It is effective at very low levels, so only small amounts are needed to protect fat-rich foods.¹

What foods contain Tertiary-butylhydroquinone (tbhq)?

In the United States, TBHQ is permitted as a direct food additive to protect edible fats and oils, and in foods that contain added fats and oils, with a maximum of 0.02% based on the fat or oil content.² That means you may find it in refined oils, shortenings, and packaged foods that contain those fats (for example, some snack foods or baked goods).

What can replace Tertiary-butylhydroquinone (tbhq)?

There are several alternatives, depending on the recipe and shelf-life needs:

• Natural vitamin E extracts such as tocopherol-rich extract or alpha-tocopherol
• Extracts of rosemary
• Ascorbic acid derivatives like ascorbyl palmitate and synergists such as citric acid
• Other synthetic antioxidants: propyl gallate, butylated hydroxyanisole (BHA), or butylated hydroxytoluene (BHT)

How is Tertiary-butylhydroquinone (tbhq) made?

TBHQ is made by reacting hydroquinone with a tert‑butyl source (such as isobutylene or tert‑butyl alcohol) in the presence of an acid catalyst. This process attaches a tert‑butyl group to the hydroquinone ring, creating an effective phenolic antioxidant.³

Is Tertiary-butylhydroquinone (tbhq) safe to eat?

Food-safety authorities have evaluated TBHQ and set strict limits on its use. In the European Union, the European Food Safety Authority (EFSA) established an acceptable daily intake (ADI) of 0.7 milligrams per kilogram of body weight per day, concluding that TBHQ is safe at approved levels in food.¹ In the United States, TBHQ is authorized for specific uses with upper limits to ensure very low exposure from the diet.²

Note: ADI stands for “acceptable daily intake,” which is the amount that can be consumed daily over a lifetime without appreciable health risk.

Does Tertiary-butylhydroquinone (tbhq) have any benefits?

Using TBHQ helps keep oils and oil-containing foods stable, reducing rancid flavors and aroma. This can extend shelf life, stabilize quality during shipping and storage, and help reduce food waste.

Who should avoid Tertiary-butylhydroquinone (tbhq)?

• People who prefer to minimize synthetic additives can choose products using alternatives such as tocopherols or rosemary extract.
• Anyone advised by a healthcare professional to avoid certain additives, or to limit intake of packaged, oil-rich foods, should follow that guidance.

Myths & facts

• Myth: “TBHQ is basically lighter-fluid butane.” Fact: TBHQ is a different molecule. The term “butyl” refers to a four‑carbon group found in many safe and common substances; TBHQ is a phenolic antioxidant, not a gas.³
• Myth: “TBHQ is unregulated.” Fact: In the U.S., its use is regulated and capped at not more than 0.02% of the fat or oil in the food.²
• Myth: “You can’t tell when TBHQ is in a product.” Fact: U.S. labeling rules require chemical preservatives, including antioxidants, to be listed by their common name and function in the ingredient statement.⁴

Tertiary-butylhydroquinone (tbhq) in branded foods

On U.S. labels, look for “TBHQ,” “tertiary‑butylhydroquinone,” or similar wording in the ingredient list, often near the oils or at the end of the list with other antioxidants. By regulation, when used as a preservative, it must be declared by name along with its function, such as “to preserve freshness” or “antioxidant.”⁴

References

Footnotes

1. Opinion of the Scientific Panel on Food Additives, Flavourings, Processing Aids and Materials in Contact with Food on TBHQ (E 319) — EFSA. https://www.efsa.europa.eu/en/efsajournal/pub/84 ↩ ↩²

2. Tertiary butylhydroquinone — 21 CFR 172.185. https://www.ecfr.gov/current/title-21/chapter-I/subchapter-B/part-172/section-172.185 ↩ ↩² ↩³

3. Tert-Butylhydroquinone (TBHQ) Compound Summary — PubChem (NIH). https://pubchem.ncbi.nlm.nih.gov/compound/16043 ↩ ↩²

4. Food labeling; declaration of spices, flavorings, colorings, and chemical preservatives — 21 CFR 101.22. https://www.ecfr.gov/current/title-21/chapter-I/subchapter-B/part-101/section-101.22 ↩ ↩²