What is Butylated Hydroxy Toluene (BHT)?
Butylated Hydroxy Toluene (BHT) is fat soluble synthetic compound widely used preservative in foods by food industries. Its function is to provide protection to oil in food products to get oxidized and become rancid.
Apart from acting as preservative in food products, BHT is also used because of its anti-microbial activity and its anti-oxidant property. It guards the colour, flavour of the food. BHT is used to preserve various packed food materials like chips, butter, cereals, preserved meat, beer, baked goods, pharmaceuticals etc.
Butylated Hydroxytoluene is an organic chemical composed of 4-methylphenol modified with tert-butyl groups at positions 2 and 6 (PubChem). It appears as white to pale yellow in colour.
Synonyms: Dibutlyhydroxy toluene
Molecular Formula: C15H24Oor C6H2(OH)(CH3)(C(CH3)3)2
History of Butylated Hydroxy Toluene BHT
BHT has been added to food products due to its property of anti-oxidant from several years. Oxygen reacts with BHT rather than oxidizing fats or oils, thereby protecting it from spoilage.
Commercial Preparation of Butylated Hydroxy Toluene (BHT)
Phytoplankton, including the green algae Botryococcusbraunii, as well as three different cyanobacteria (Cylindrospermopsisraciborskii Microcystis aeruginosa and Oscillatoria sp.) is capable of producing BHT.
BHT is prepared by the reaction of p-cresol (4-methylphenol) with isobutylene (2-methylpropene) catalyzed by sulfuric acid.
Uses of BHT:
- BHT is used as a food additive.
- It is used as a preservative in food products including several cereals & dried soups..
- It is used in food products for its anti-microbial activity & anti-oxidant activity.
- It is used as a de-foaming agent used with yeast.
- It is used in food packaging and animal foods.
- It is used in the formulation of cosmetics & rubber.
- It is also used in several medicines.
- It is used in personal care products.
- It is used as fuel additive.
- It is used in laboratory chemicals.
- It is used as plasticizer and solvent for cleaning.
Advantages of BHT:
- BHT is a potent anti-oxidant; hence it prevents the product to become rancid.
- It remains stable at high temperature.
Disadvantages of BHT:
- National Toxicology Program (NTP) has concluded BHT is carcinogenic to humans, based on their animal research.
- Some studies have also shown that BHT stimulates production of cancer causing enzyme.
- BHT is safe in low doses, but carcinogenic in high doses.
Side effects of taking excess amount of BHT:
- It has been known to impair blood clotting, when consumed in high quantity.
- It promotes tumour.
FDA Approval on BHT:
The Food and Drug Administration (FDA) categorizes BHT as food additives as GRAS (generally recognized as safe), which means they are considered safe for their intended use in specified amounts.