29 Apr WHOLEFOODS ARE ALWAYS BEST – A REPORT ON THE FOOD ADDITIVE BUTYLATED HYDROXYTOLUENE.
Food AdditivesFood additives are chemical substances added to foods to improve flavour, texture, colour, appearance and consistency, or as preservatives during manufacturing or processing. Herbs, spices, hops, salt, yeast, water, air and protein hydrolysates are excluded from this definition. Butylated hydroxytoluene (BHT), also known as dibutylhydroxytoluene, is a fat soluble organic compound chemically derived from phenol, that is useful for its antioxidant properties. Its action which is likened to that of Vitamin E, is often added to foods as a preservative due its ability to prevent oils, fats and shortenings from oxidative deterioration and rancidity. Conversely, BHT is also used in Non-Food products such as cosmetics, pharmaceuticals, rubber, oil, jet fuels and petroleum products to slow down the autooxidation rate of ingredients. More recently it has been used in medicine to treat genital herpes and acquired immunodeficiency syndrome (AIDS) as it works by damaging the protective outer layer of viral cells which may keep the viruses from spreading and causing more harm.
BHT is a white crystalline powder but will turn yellow in colour in the presence of foods containing iron. It is generally odorless but may potentially have a slight aromatic smell. More often than not, BHT is used as an antioxidant in foods in conjunction with Butylated Hydroxyanisole (BHA), because the two are synergistic in their actions.
BHT is combustible in nature and presents health hazards when exposed directly to eyes, skin or is ingested/inhaled. BHT must be stored in an air tight container that is free from light, heat and moisture to prevent discolouration and loss of activity. It is phenolic in its essence and thus undergoes reactions typical of phenols. Contact with strong oxidizing agents may cause BHT to spontaneously combust due to its incompatibility with such agents.
Although BHT was initially cultivated as an antioxidant product for use in petroleum and rubber products, the Food and Drug Administration granted approval for its use in food and food products in 1954, hence, BHT is now widely used as an additive in food to reduce the oxidative deterioration that results in rancidity, food spoilage, losses in colour and flavour and a lesser nutritional value.
BHT promotes shelf life of food by interfering with the propagation step in the mechanism of oxidation. The antioxidant effect “arises from the presence of a hydroxyl group attached to an aromatic ring substituted with methyl groups”, thus allowing a hydrogen atom to be donated from the hydroxyl group to a fatty radical and putting a stop on the foods degradation.
BHT is best suited in foods containing a high fat or oil content because it is insoluble in water and is also more effective as an additive in animal fat rather than vegetable oil because it is volatile and distilled under certain food processing conditions. BHT is therefore unsuitable for use alone in an oil particularly when foods that are high in moisture are being fried. BHT has a high-temperature stability and imparts this trait when used in baked goods, fats or shortenings.
BHT is best used in conjunction with Butylated Hydroxyanisole (BHA) because it has a synergistic effect, however BHT has a greater steric hindrance than BHA because BHT contains two tert-butyl groups encircling the hydroxyl group.
Below is a list of common foods containing BHT:
- Active Dry Yeast
- Cake Mixes
- Cereals and Cereal Based Snack Foods
- Glazed Fruit
- Emulsion Stabilizers for Shortening
- Ready Meals
- Essential Oils
- Dehydrated Meat
- Sausage, poultry and meat products
- Snack Foods
- Chewing gum
- Frying oils and frying fats excluding olive pomace oil
- Dehydrated soups, broths, potatoes
- Potato Chips
There have been many studies conducted on the use of BHT but as can be seen in toxicology majority have been carried out on animals rather than humans. The few studies that were performed on humans, identified a lower percentage of excretions and further problems including symptoms of headaches, back pain, diaphoresis, asthma and more. Furthermore, there has been incidences where people were either intolerant to BHT or allergic and although it was suggested that those with those responses possibly had an imbalance in their body’s fat metabolism overall the results were not conclusive.
On the other hand, there have also been studies that claim BHT has the opposite effect in that they may even be anti-carcinogenic, but it is more likely that the anti-carcinogenic effects are the result of naturally occurring antioxidants and not synthetic materials used to promote unnatural shelf life. Overall, negative sides effects have been identified in high doses of BHT but if the dose is reduced what is the result of then long-term exposure? This is yet to be studied.
The toxicology studies determined that the ADI was 0-0.3 thus the TMDI and EDI theoretically fall within the ADI range making it safe for consumption in small amounts. When truly assessing the risks involved with the antioxidant BHT it is important to note that the average Australian does not eat complete natural wholefood products prepared fresh in their home every single meal, every single day and are thus more likely to be exposed to BHT most days for their entire lives. Even if the individual was more health conscious and diligent with their food choices it is highly likely that they’d still encounter BHT in the form of nonfood products like medicines, packaging and cosmetic products that haven’t been considered.
It is also important to note that the ADI will vary between countries, age, sex and lifestyle and even though there is an ADI in place it is almost impossible to track one’s exact consumption and whether it will fall in line with their genetic makeup and their requirements to maintain homeostasis for optimal function. Truth be told, food manufactures are seeking to maximize profits through longer shelf life and not deliver consumers their best health.
The risks associated with BHT have been recognized and there are plans for a reduction in its allowable usage amount over the coming years it is still recommended that consumers do their best to eliminate or at best reduce the amount of BHT they ingest. One sure way to do this is to eliminate cereal and cereal based products which are the more common products containing BHT, vegetable oils containing BHT and chewing gum. Consumers are advised to read food labels to identify if BHT is listed and to prepare as many fresh meals in the home as they can.