|See Also||Clinical Nutrition|
Food colourings are a type of additive used to enhance the appearance of a food product. Specifically they are used to: offset colour loss due to exposure to light, air, temperature extremes, moisture and storage conditions; to correct natural variations in colour; to enhance colours that occur naturally; and to provide colour to colourless items. Processed foods such as cookies, candy, cakes, sports drinks, margarine and cheeses tend to contain the highest amount of colour additives.
Colouring is also used widely in food products marketed to children such as candy, soft drinks and breakfast cereals to help increase the products' visual appeal on shelf, excite the senses and bump up the perceived fun factor.
Types of Food Colourings
Natural Food Colourings
Throughout the ages, food dyes have been produced from natural sources such as vegetable leaves, pomegranate and saffron. Some naturally occurring examples include:
|Anthocyanins||orange-red, to red to blue||berries, grapes, apples, roses, hibiscus, red cabbage, sweet potato|
|Betacyanins||red||red beets, red chard, cactus fruit, bougainvillea|
|Caramel||beige to brown||heated sugars|
|Carotenoids||yellow to orange to red||saffron, tomatoes, paprika, corn, butter, palm oil, marigolds|
|Chlorophylls||green to olive green||green plant leaves|
|Riboflavin||yellow||vegetable leaves, milk, eggs, organ meats, malt|
|Turmeric||yellow||Curcuma longa rhizome|
The coloured components of these natural substances are often provided in a highly purified form so that they can be easily and safely reproduced. They can also be formulated into solid and liquefied materials, which helps to increase their stability.
Synthetic Food Colourings
While natural colourants are generally a safer alternative, today the majority of modern colouring is derived from coal tar or petroleum or created by chemical synthesis by food manufacturers because it’s more economical.
Synthetic food colour additives currently approved for use in Canada include: Allura Red, Amaranth, Brilliant Blue FCF, Citrus Red No. 2, Erythrosine, Fast Green FCF, Indigotine, Ponceau SX , Sunset Yellow FCF, and Tartrazine.
- Allura Red
- Allura red, (E129) is an artificial red azo dye that goes by several names including: Food Red 17, CI 16035 and FD&C Red no.40. It is most often used in soft drinks, cosmetics, candy, chewing gum and condiments. This additive was introduced in the early 1980s to replace Amaranth, a dye that was banned by the U.S. Food and Drug Administration during that time. Allura red is currently banned in Denmark, Belgium, France, Germany, Switzerland, Sweden, Austria and Norway.
- A study has shown that allergic reactions occurred in 15% of the population who consumed food products containing Allura Red. In this test, all 52 participants who had been suffering from hives and, or rash for four weeks or more were placed on an elimination diet and all potential sources of allura red were removed. Following three weeks of no symptoms, participants were ‘challenged’ orally with allura red and symptoms were monitored. Of those tested, 15% showed a positive reaction such as reoccurrence of rash or hives.
- Amaranth is derived from the small herbaceous plant of the same name. It is a purplish-red coloured synthetic coal tar or azo dye that is often used in pie fillings, jams and jellies, packaged cake mixes, soups, gravies, and ice creams. Amaranth is banned in Norway, the United States, Russia and Austria, and has very restricted use in France and Italy where it is only permitted to provide colour to caviar.
- Brilliant Blue FCF
- Brilliant Blue FCF is a synthetic coal tar dye often used in conjunction with Tartrazine to produce various shades of green. It can be found in canned peas, dairy products, sports drinks and candy. This dye is currently banned in Austria, Belgium, Denmark, France, Germany, Greece, Italy, Norway, Spain, Sweden and Switzerland.
- Citrus Red No. 2
- Citrus Red No. 2 is an orange to yellow solid or a dark red powder that is not water-soluble, but is readily soluble in many organic solvents. It is most commonly used to color the skin of oranges.
- This dye has been listed as an IARC Group 2B carcinogen, meaning that it is "possibly carcinogenic to humans".
- Erythrosine (E127) is a cherry pink reddish coloured synthetic coal tar dye that is used in canned cherries and fruit, candy, cookies, chocolates, cake decorating gels, popsicles, luncheon meats, paté, stuffed olives and canned crab. It is also used to colour pastachio shells and as a biological stain, a dental plaque disclosing agent and a radio-opaque medium. Depsite concerns about its potential carcinogenic nature, Erythrosine is still used widely throughout the world.
- During food processing Erythrosine partly degrades when temperatures reach above 200°c and iodine is released. Consequently there is concern that Erythrosine can have an adverse effect on thyroid activity by increasing thyroid hormone levels which can in turn result in a hyperthyroid state. This dye was shown to cause thyroid cancer in rats in a study conducted in 1990.
- Fast Green FCF
- Fast Green FCF (E143), is a sea green coloured food dye also known as Food green 3, FD&C Green No. 3, Green 1724, Solid Green FCF, and C.I. 42053. This dye is used in canned vegetables, jellies, dry bakery mixes, sauces and desserts and is currently prohibited for use in countries within the European Union.
- This synthetic dye is poorly absorbed by the intestines, and has been found to have tumorgenic effects in experimental animals, as well as mutagenic effects in both experimental animals and humans. Its use in its undiluted form is associated with the risk of irritation of the eyes, skin, digestive and respiratory tracts.
- Indigotine is a blue synthetic coal tar dye that is commonly used in ice cream, candy, baked goods and cookies. It is also added to drugs in tablet and capsule form, and used diagnostically to check for coloured urine in kidney function tests. This dye is currently banned in Norway.
- This dye should be avoided by anyone with allergies as it may cause skin sensitivity, itching and a skin rash similar to that created by stinging nettles. It is also contraindicated in people with high blood pressure and breathing problems.
- Ponceau SX
- Ponceau SX, which is commonly known as FD&C Red No. 4, is permitted in Canada in or on fruit peel, glazed fruits and maraschino cherries at a maximum level of 150 parts per million. This dye is currently banned in Norway and The United States.
- Sunset Yellow
- Sunset Yellow, also known as E110, Orange Yellow S and Yellow 6, is a synthetic coal tar and azo dye and is used in fermented foods that must be heat-treated. It can be found in foods such as packet soups, breadcrumbs, ice cream, canned fish, lemon curd, hot chocolate mix, some jams and jellies and many medications.
- In some individuals, consumption of Sunset Yellow synthetic dye can lead to the development of hives, hyperactivity, nausea, abdominal pain, nasal congestion and rhinitis.
- Some studies have shown a link between the consumption of Sunset Yellow dye and chromosomal damage and an increase incidence of tumors in laboratory animals. However, the World Health Organization’s review of Sunset Yellow found no evidence of increased tumour incidence in both short term and long term studies conducted on rats, guinea pigs, hamsters and dogs. As such they established the acceptable daily intake (ADI) at 2.5 milligrams/kilogram bodyweight per day. World Health Organization.
- Of all of the synthetic colourants, Tartrazine (FD&C yellow dye #5) is the most widely used. It is added to virtually every packaged food product and many over the counter drugs such as antihistamines, steroids, antibiotics and sedatives. In fact, in the United States the average daily consumption of certified dyes per capita is 15 mg, of which 85% is tartrazine. This percentage is even greater in children due to the high levels of synthetic dyes used in the production of foods targeted to this group.
- Tartrazine is banned in Norway and Austria.
- Adverse reactions to the consumption of Tartrazine include: allergies, urticaria (skin rash), rhinitis (runny nose), asthma, migraines, purpura (purple skin bruising) and systemic anaphylaxis (shock). This intolerance appears to be more common in people with asthma or a sensitivity to aspirin.
- While allergic reactions holds true for all synthetic food colourings, the Health Canada department highlighted the food colouring tartrazine as a primary irritant and allergen as 0.1 to 10 out of every ten thousand people (0.01% to 0.1% of the population), has a sensitivity to Tartrazine.
- Allergic Reaction: Health Canada noted there is evidence that certain food colours can elicit an allergic response or allergic-type sensitivity in certain individuals, especially those that suffer from asthma, allergies, sinusitis, rhinitis or have a sensitivity to aspirin.
- Skin Reactions: Food colourings are associated with a number of skin reactions including: itchiness, rash, urticaria or hives,
- ADD/ADHD: The use of colour additives has been linked in some scientific studies to hyperactivity in children. Attention Deficit or Hyperactivity Disorder (ADD/ADHD) is a condition that becomes noticeable in some children around the age of preschool or early school years. Children affected by this disorder have difficulty paying attention and/or controlling their behaviour.
- Throughout the 1970’s several scientific papers claimed that between 30 and 50% of children with hyperactivity disorder improved when placed on a diet free of artificial colours and salicylates. Attempts to replicate these findings throughout the 1980’s presented varied results; some studies showed a clear link, while others did not.
- More recently, in 2007 a study in a British scientific paper, The Lancet reported a link between consumption of fruit juices containing colour additives and an increase in signs of hyperactivity in children of 3 and 8-9 years of age.
- A 2010 analysis of past research on links between food dyes and health by the Center for Science in the Public Interest (CSPI) also found compelling evidence that ingestion of artificial dyes can contribute to hyperactivity, restlessness and attention problems in some children - particularly those with ADHD.
- Other Conditions: Conditions such as headaches, migraines and hypertension have also been associated with food colourings.
- Cancer: Some food colourings are carcinogenic and tumerogenic, which means that they are suspected or known to contribute to the development of cancer.
- In Canada, colour additives are considered food additives and are governed under the same regulations as food additives in Division 16 of the Canadian Food and Drug Act and Regulations. In order to be approved, toxicological and safety information must be submitted to Health Canada.
- The Canadian Food and Drug Regulations currently require that food colours be declared in ingredient lists, however for most foods, section B.01.010 (3)(b) of the Regulations permits the use of the general term "colour" to specify one or more food colours, and states that “manufacturers may voluntarily declare individual colours by name at their own discretion.”
- Requiring that food colouring be clearly identified on processed food labels will help close the gap between requirements in Canada and International Standards. In the U.S., the Food and Drug Administration requires certified synthetic colours to be declared. Australia, New Zealand and European Union members require all food colours to be declared either by their common names or numerical identification numbers, and the UK has called for the voluntary ban of several synthetic colours including: Tartrazine, Quinoline Yellow, Sunset Yellow, Carmoisine, Ponceau 4R and Allura Red.
Following are the permitted synthetic colours in Canada and their corresponding names in the United States and Europe.
|Allura Red||FD & C Red #40||129|
|Amaranth||FD & C Red #2||123|
|Erythrosine||FD & C Red #3||127|
|Ponceau SX||FD & C Red #4||125|
|Citrus Red No.2||Citrus Red #2||121|
|Tartrazine||FD & C Yellow #5||102|
|Sunset Yellow FCF||FD & C Yellow #6||110|
|Fast Green FCF||FD & C Green #3||143|
|Brilliant Blue FCF||FD & C Blue #1||133|
|Indigotine||FD & C Blue #2||132|
Following are the permitted natural colours in Canada and their corresponding name in Europe.
- Food Science Department of The University of Guelph, http://www.uoguelph.ca/foodsafetynetwork/artificial-colours
- Gullett, Elizabeth A. (1992) Color and Food. In Encyclopedia of Food Science and Technology, edited by Y. H. Hui, vol. 1. New York: John Wiley & Sons.
- Farrer KTH (2000) "Food Additives" In The Cambridge World History of Food, edited by Kenneth F. Kiple and Kriemhild Coneè Ornelas, vol2. Cambridge University Press.
- Canadian Food Inspection Agency, Food Colours, http://www.inspection.gc.ca/english/fssa/labeti/decisions/coloure.shtml
- UK Food Guide, http://www.ukfoodguide.net/e129.htm
- Food Science Department of The University of Guelph, 
- Agents Classified by the IARC monographs, http://monographs.iarc.fr/ENG/Classification/ClassificationsGroupOrder.pdf
- Fischer Scientific, Material Safety Data Sheet, Fast Green FCF, http://fscimage.fishersci.com/msds/60270.htm
- Sunset Yellow FCF (WHO Food Additives Series 17). Retrieved from http://www.inchem.org/documents/jecfa/jecmono/v17je29.htm.]
- Murry Michael T (1993) The Healing Power of Foods: Nutrition Secrets for Vibrant Health and Long Life Prisma Publishing.
- Health Canada, (Feb 2010) Letter - Health Canada Proposal to Improve Food Colour Labelling Requirements 
- McCann D, Barrett A, Cooper A, Crumpler D, Dalen L, Grimshaw K, Kitchin E, Lok K, Porteous L, Prince E, Sonuga-Barke E, Warner JO, Stevenson J (2007) Food additives and hyperactive behaviour in 3-year-old and 8/9-year-old children in the community: a randomised, double-blinded, placebo-controlled trial. The Lancet;370(9598):1560 – 1567. doi:10.1016/S0140-6736(07)61306-3
- Food Standards Agency [http://search.food.gov.uk/search?site=default_collection&client=fsa_gov&output=xml_no_dtd&oe=UTF-8&ie=UTF-8&proxystylesheet=fsa_gov&q=food+colouring&submit.x=0&submit.y=0
- Canadian Food Inspection Agency, Food Colours: Permittted Synthetic Colours in Canada http://www.inspection.gc.ca/english/fssa/labeti/decisions/coloure.shtml
- Canadian Food Inspection Agency, Food Colours: Permittted Natural Colours in Canada, http://www.inspection.gc.ca/english/fssa/labeti/decisions/coloure.shtml