Butylated Hydroxytoluene (BHT)
Antioxidant
Installed 09 Oct 2005. Latest update 18 May 2013. New or changed text is in bold.
The (fat-soluble) crystaline phenolic antioxidant butylated hydroxytoluene (BHT) was patented in 1947 and received approval for use as a food additive and preservative by the U.S. Food and Drug Administration in 1954.(1)
In 2008 researchers in Taiwan reported finding that BHT is produced naturally by four different kinds of freshwater phytoplankon.(2)
Microscopic Image of BHT (White Crystalline Powder) Showing Individual Crystals
(Courtesy: Jack Reed, Department of Entomology, Mississippi State University)
The following is a somewhat unorthodox stick figure drawing of a BHT molecule.
Stick Diagram and Formula for BHT Molecule
Grey = Carbon; White (and match heads) = Hydrogen; Red = Oxygen
BHT molecules host seven CH3 methyl groups. A methyl group consists of three hydrogen atoms bonded to a carbon atom which is linked to the remainder of a molecule.(3) In the colored stick diagram, the methyl group hydrogen atoms are shown as match heads to remind readers of their roles as hydrogen-donor free-radical scavengers. Their anthromorphic motto might be "Light my fire!" (These last two sentences are written by a non-chemist. It may turn out that something else about the molecule causes it's radical scavenging activity. Input is welcome!)
Structural comparisons of Antioxidants BHA, BHT and Vitamin E
John J. Manura(4) summarizes a gas chromatography/mass spectrometry (GC/MS) study to measure volatile and semi-volatile organics (including BHA and BHT) in food and pharmaceutical packaging. He cites an earlier study(5) focused on quantifying BHA and BHT in food cereals.
Comparing the Antioxidant Activity of BHT with Two Other Antioxidants
Here is a copy of Table 2 in the article from which the two preceding statements were drawn.
Table 2. Antioxidant activity of Berberis vulgaris extracts, BHT and Vitamin E using the Thiobarbituric acid method (TBA).